Seriously some of these tropes explain the girls hilariously well. Just wanted to share all some of my favorites since most folks probably won’t even click on the link. Bolded stuff (in parentheses) are all my own comments.
Butt Monkey: Despite being the leader, Kanako is constantly bullied by the other members due to her idiocy.
Fangirl: Of Atsuko Maeda from AKB48. (I wasn’t aware of this prior to reading said tropes page)
Forehead of Doom: Her nickname, the dekoppachi, is no joke, What's more, back when they were still an indie group, her hairstyle highlighted it even further (nowadays it's often obscured by her bangs).
Gratuitous English: Her first solo (She did say back then that her English was lousy.)
Smiling sun with your love
Sweetest love with your smile
Kick Chick: Her great leg strength is often put to good use in many fighting skits. Also, there is actual kicking choreography in "Pinky Jones".
Terrible Artist: Becomes a running gag whenever she draws something.
Passionate Sports Girl: She excels at sports, has been learning gymnastics since age 3, and has becomes a regular player on basketball teams.
Tsundere: Her official English introduction says she is one, although she isn't an apparent tsundere. The only denial she always makes is about her stupidity.
Artifact Title: Everyone's Little Sister. She was indeed the youngest in the group's first formation in 2008, before Ahrin took the title. She also grew to be a lot taller than everyone else over the years (in 2010 she was shorter than Kanako), and after cutting her hair short, her transformation into abadass had finally completed. (Badass is right to the point where she’s my 2Oshi nowadays)
Big Eater: So much so that her special segment in their TV show involves her eating food, and any lyrics that mention food are Shiori-exclusive. As a challenge, she was able to finish 62 cups of Wanko Soba noodles in 5 minutes. Yet all that food just seems to disappear in her stomach, and she has been able to maintain her slender stature as a result, and has even grown taller.
Fight Magnet: Her antics always leads to a fight, according to Kanako. (Fact. Especially if you watch a lot of the BTS footage from the concerts XD)
Hates Being Alone: When the girls had to stay in a hotel during their tours, she was the only one who couldn't stand being alone. She would always barge into Kanako's room, demanding to share her bed. This story became the basis of their duet song "Single Bed". (The cutest damn song. I hope we get to see more member specific songs on the upcoming albums.)
Jack-of-All-Trades: She can sing, dance (she can even imitate the entire choreography of Ahrin's solo song), do ventriloquism, play piano, perform acrobatics, voice act, do rakugo (Japanese story telling), imitate the other member's signatures, she's smart, she's athletic, and finally, she can throw a marshmallow in the air and catch it with her mouth.
She's Got Legs: ...since mid-2012, anyway. (Indeed. Legs indeed.)
Aarin/Ahrin/howeverthehellyouwanttoromanizeit
Berserk Button: "Call me Ahrin not Sasaki!" (Fact. There’s even a whole song dedicated to this.)
Catchphrase: "Ahrin Da Yo!" (Have fun getting it out of your head when you hear it.)
Image Song: Her solo songs, "Santa-San" and "Ahrin ga Hankuouki", are all about this; the former is tells us about her very idol-ish traits, while the latter describes her annoyance towards her mother (Ahrin's Mama as she called her) and desire to rebel.
Kid-Appeal Character: Annoyingly cute yet still lovable. Her Ahrin Robo persona also aimed for this. (I love her voice when she isn’t being all cutesy the most.)
Lucky Charms Title: All of her blog post's titles end with a star symbol. Hyadain alluded to this by choosing to have the titles of her solo songs end in the same way. (Her first solo line in Z Densetsu even has stars in the lyrics and onscreen subtitles when they performed the song on shows.)
Robotic Reveal: Played for Laughs when she revealed her robotic form, Ahrin Robo, in her skit at a 2013 children's festival. Became real when she broke a leg in 2014 and decided to use her robot persona to perform on stage. This would ultimately evolve into her becoming Ahrin Robocop. One more for the Momoclo Shout-Out list.
The Chick: She is the only member who can't perform the acrobatic gimmicks the group is known for
Third-Person Person: You're not the only one that's annoyed by it.
Cute Clumsy Girl (She even has a darn cute little lisp to match.)
Dancing Is Serious Business: While the others perform some amusing and hilarious traits in The Cast Showoff segment, she just does her random dances. (She can probably give the entirety of SKE a run for their money. Okay that’s a bit too much. But at least Team K or Team S.)
The Ditz: She even introduces herself as the little bit silly.
Kansai Regional Accent: Her family is from Osaka, and she uses Kansai dialect when talking with her family. As a nod to this, she has the Kansai region verse in "Momoclo no Nippon Banzai!"
Pint-Sized Powerhouse: She is nicknamed "The Little Giant", after all. Fun Size is in effect here as well.
Tender Tears: Can often be seen crying in live concerts, to the point of messing up her singing. Even during Akari's graduation, where everybody had the waterworks on, she managed to cry more than even Akari. (The running joke for all MomoClo concerts is that Mononofu take bets as to when Momoka will cry during the concert.)
Singing Voice Dissonance: She is the strongest vocalist of the group; her famous husky singing voice is very noticeable in her shouting solo lines, e.g. in "Mouretsu", and several of Hyadain's songs, such as "Koko Natsu" and "Wani to Shampoo" (it seems that he was positively exploiting her vocal trait). It's a little bit surprising when you hear her talk, though, because... (She honestly has the strongest vocals. Like. Yo. Just hearing talk? You’d never guess.)
Speech Impediment: ...Her lisp is beyond help. Even when composing "Kaito Shojo", Hyadain decided to change the common pronunciation of Four, shi, into yon because she can't spell it well. (Like I said. It adds to the cute factor.)
Animal Motifs: ...Alien. (Uh. Um. Actually? Yeah... Pretty accurate at times.)
The Determinator (Yeah. This one for sure. It’s to the point where she can single handly swing the group back into things when Kanako fails.)
Graceful Ladies Like Purple: Well, while her antics are far from graceful, her solos are all traditional Japanese enka songs with Yamato Nadeshiko-esquelyrics, and she wears beautiful kimonos along with them.
The Leader: Was formerly the leader long before Momorio Clover was officlialy formed, but voluntarily stepped down due to personal issues.
The Prankster (Fact. Apparently it was her idea to get the staff together during Toujinsai 2014 practice and pie Kanako in the face with 21 pies, referencing how old Kanako was turning. Right after herself and the others put on a obscene amount of lipstick and gave Kanako big old kisses on the face. And then during the Saitama Super Arena Concert “Shining Snow Story” she trolled pretty much everyone during their recording of pre-concert messages to the fans. She harassed Kanako, maintained skinship with Momoka’s thighs (much to Momoka’s dismay as she couldn’t maintain composure while recording), talked loudly in the background while Shiorin was recording and tossed ice down the back of Aarin’s shirt. The Aarin moment was comedy gold to say the least.)
Perpetual Smiler: One of her Fan Nicknames is "Egao ga Ichiban" (The number one smile). (You know the Pringles catchphrase “Once you pop you can’t stop? Same deal when you see Reni smile!)
Purple Is Powerful (Her nickname “The Electric Girl” is pretty much evident of this.)
Supernatural Is Purple (The running gag is to send her into the haunted house on Momoclo-Chan)
And because she’s on there...
A Wild Rapper Appears: She excels at rapping and always in charge of the rap parts (and this is why the foreign fans love her so much), to the point that many of their songs in Z era didn't get rap parts compared to their songs back then.
Big Ol' Eyebrows: She was often called "Mayuge" (which means "eyebrow"). She even acknowledged that her eyebrows were her main charm point. (This is even referenced in the Z Densetsu song. In the second verse the announcer “accidentally” calls out “BLUE!” as a nod to her and the girls motion their fingers towards their brows with two fingers taking a jab at her famously thick eyebrows.)
Character Title: Her graduation song, "Akarin e Okuru Uta", which means, "A song for Akarin".
Fan Nickname: "Mega". This comes from her tall stature compared to the rest of members. (She literally towered over the rest.)
The Fashionista: She was a fashion and commercial model even before her inclusion to the group. After her graduation, she began to focus more on her model career.
The Face: She often handled the MC part for their reality show, Momoclo-Chan and their live performances. She is their Cool Big Sis, after all.
Internal Homage: Even after her departure, she is regularly referenced elsewhere in their acts. This is probably because her graduation marked a big change in the group's history.
The lyrics for "Z Densetsu" references Akarin with the narrator's announcement of "BLUE!", which prompted the group to answer with a confused "ah?" and place their fingers on their eyebrows.
(As I mentioned earlier...)
A popular fan theory said that the slow ballad songs from around the Battle and Romance era, "Kiminoato" and "Shiroi Kaze," are all dedicated to Akari; the overall lyrics place importance on a person that had to leave after they made a lot memories together, and they had to smile and move on. Additionally, both songs are composed by same person, and the word kimi ("you") in the lyrics is written with katakana rather than usual hiragana, implying it refers to a particular someone. During the 2011 and 2012 Momoiro Christmas concerts, both songs were presented with all blue stage lighting.
In the end of the medley song in their first Kohaku performance (when they finally reach their dream), they sang their old (six person) version lyrics of Kaitou Shojo that lists their names. When it came to Akarin's, they simply pointed to the camera.
Passionate Sports Girl: She has an aerobics qualification and, just like Kanako, has an extremely flexible body, as seen in "Mirai E Susume"'s choreography. This is probably one reason why they're so close.
This was also lampshaded in her 2011 movie, Cheerfu11y, where she got to display her talents as a Cute Bookworm constrained to join a cheerleader team.
Team Mom (The definition of it. Especially at the end of her graduation concert when the group was renamed “Z” and the remaining members were panicking.)
True Companions: Especially with Kanako. It's also noted that the group keeps in touch with her to this day (They're even still at the same office!). After their performance in Kohaku, Kanako called her and asked her if she was crying. She was.
Trying Not to Cry: During her graduation. She didn't succeed, as she ended up crying a lot, even after the graduation ended, mainly because of the surprise farewell song, which reduced her to blubbering in the rest of their songs. At the end of the concert, she went with a Tearful Smile when saying goodbye to the fans. (Even nowadays I hear other Mononofu state that they’ve never watched the concert or that they refuse to. And after watching it for myself, it wasn’t easy even for myself as a newer Mononofu, I can see why. It has a lot of impact compared to all the graduations I’ve endured as a 48G fan.)
The Unfavourite: The entire reason why Akarin left the group. She felt that she didn't have the personality to be an idol. She also said that she had doubts about being in Momoiro Clover, and there were even times where she had started to dislike being in the group. It is also said that she always had the shortest handshake queue in the events that providing handshake session. (Honestly I’ve heard the rumors. It doesn’t help documentation of these handshake events from those days are scarce. But it’s kinda painful to hear and read about considering she really was a huge, huge, huge part of the group.)
