This is less of a question and more of a polite request but please share all your Mami and/or Amasawa thoughts and/or headcanons.
➤ Mami always adored basketball. All because of the manga she read. While she knew she joined the team late and was aware how terrible her skills would be, she still wanted to join to show her interest in such things, only to be looked down on about her skills. It's already bad enough that she is getting bullied by her team, but to be judged by them with her skills as a basketball player made her doubt herself a little too much. Even with Yagami's reassuring words, she still has her doubts from time to time. Not as bad as it used to be.
➤ I love to think she polished her skills outside the team, playing on her own when no one is looking. There would be a few hours out of her day that she would go off and try to play. Just so she doesn't fall into being judged for her skills. Even if she did become on good terms with her team members, she still wanted to do this.
➤ I am taking what Yagami had said in that scene where Matsui apologized and applying full force, even after the game. The thing is, I am conflicted how on to write this, which I might push this conflict into this thought. Mami is conflicted with her feelings. On one hand, she shouldn't forgive Matsui and his friends for what they have done. She knew that their bullying left her with more doubts about herself. At the same time, they did apologized or I'm assuming everyone else apologized off-screen since we only saw Matsui apologized on-screen. And with them stepping in to stop another kid being bullied in the end, yeah, it is conflicting for Mami. I wouldn't say she is entirely on good terms with Matsui and his friends. Let alone entirely forgiven them for what has happened. Given her nature, I am sure she did manage to forgive them. Not 100% though. She only did so because they apologized and actually carried out with their changed behavior. Even then, she wants nothing to do with them. Despite their scene together at the end, I still believe she would rather not deal with them.
➤ I'm putting a bit of a twist to Mami. Much like how she took interest in basketball because of a manga she loved, she took interest in being a detective because of Yagami. He was - and probably still is, given he might visit the school due to his status to the clubs - there for her. He had given her reassuring words and helped her out in times of need when no one else did. I am still in debate if I wanted to make her quit the basketball team because she wants nothing to do with the team any longer and joined the MRC or continued to show up on the team because she's not going to back down from her interest.
Either way, I would say she is best friends with Amasawa. I like to think Amasawa heard about what's going on and saw how much Yagami helped Mami. So Amasawa would often visited Mami and befriended her. Their friendship blossomed to where they would be at each other's houses from time to time. Sleep-overs, studies together, etc. As far as we know, Amasawa doesn't have a best friend. As much as she could claim her brother as a best friend or Yagami, she would rather have a friend outside her family and advisor. Correction, the two has another best friend and that's Kotoko. The trio do understand each other's situations to an extent and all were helped by Yagami. With that common grounds, the trio became close friends.
➤ Mami actually lives with her father, but he isn't aware that she was being bullied. She didn't want to add more stress with him. He's a single father, raising up his only daughter. A hard-working one too. So, he's constantly at work, trying to provide for the two.
➤ Before everything that happened with Sawa, I would like to say Mami used to be close with her. Mainly because she had no one else to turn to. Plus, Sawa understands completely how Mami feels and her situations. After all, Sawa did witness this before. After hearing Sawa's death, Mami felt hollow. She couldn't process what happen. While she didn't show it on-screen exactly, she grieved for her teacher. She can't walk in and be delighted to see her teacher any longer.
➤ Amasawa always held interest in anything mystery. It's why she joined the MRC. One of the things that driven her to do so is Sherlock. She enjoyed reading the book as well as anything to do with the character. So, yes, she would be often seen watching stuff or reading about Sherlock. Even going as far as reading anything mystery-related. And with Yagami as her advisor and an actual detective, she set her eyes on being a detective herself. If he's not around, she could be seen at Yokohama 99 with both Sugiura and Tsukumo. She may be a bit iffy on those two, but she will eventually warms up to them, especially Tsukumo. But imagine if he is the reason why she got into mangas. Between that and how Kento is, yeah, Tsukumo is getting the Amasawa siblings in the office all over him. Amasawa being the manga-reader / anime-watcher and Kento being the one to talk about games to Tsukumo.
➤ While not many do enjoy her presence, given she is always sticking her nose into other people's business, she is the detective of the school. Unofficial that is. While, yes, the school - or rather the students - can hire an actual detective, sometimes it's more fun to hire a potential detective, especially aiding in her skills as one. If it's an actual case that requires an actual detective, they will gladly do so. It comes in handy to have Yagami walking around the campus because he is in several clubs as well as having Amasawa be there to call him up. Not that anyone don't trust Yokohama 99. In fact, Amasawa will say call Y99 than call Yagami. If it is absolutely necessary, yes, she'll call him up.
➤ Amasawa actually wanted to join a sport team at one point but realized she's not the greatest at any sports. Gym was not her greatest class.
➤ I love to assume Amasawa knows who Ichiban is. Her being nosey would result in crossing paths with him at one point. For now, they only know who each other but nothing more. No friendship has blossomed. Not yet. I would love to imagine her meeting Adachi and having another detective buddy, despite him being old and being a former detective.
➤ No, I will not be taking any criticism, but Tesso will absolutely adore Amasawa. Anyone who Yagami takes under his wing is someone that Tesso gotta meet. Plus, both Tesso and Amasawa live in the same city and based off of my HC I mentioned earlier with Y99, there's no doubt she would cross paths with him. She may not be aware what he does but she knows something is off about him. She keeps being nosey yet getting no answers to her questions. Even if Amasawa would understand and not judge him based off of his position, he would rather spare her from such information.
➤ I might end up discussing this connection out with a friend since I asked her to pick up Okitegawa for me, but it is possible the two will end up becoming friends. I was telling my friend that there's no doubt that they would cross paths and befriend each other, even if Amasawa is Amasawa. The fact that Yagami is the advisor to both clubs as well as the final chapters of the school investigation substories. Yeah, they gotta be friends somehow, even if they don't always see eye to eye. More information will come soon once the discussion set sail.