Kanami, being raised by shady SAKIYAKU adults and synthetic brothers that are literally grown to ages 20-25, hasn't really had the time to talk to or bond with people her age. While she can interact with them thanks to SAKIYAKU's manipulation and blend in amongst them seamlessly, that's not the same as actually developing or forming connections with people your age so when Hexel presented Kanami with SHIELD's dossier on each villain, Daito's would immediately stick out to her when she realizes that they were the same age as each other. Obviously during the first meeting with Iker and Team Sinister, Kanami tried not to acknowledge him unless he spoke to her because she wasn't sure if she was able to talk to him without being awkward.
But when she's invited to Team Sinister meetings to discuss about projects or plans to destroy AWOL and the Defenders, she has a tendency to make her way towards Daito. She'll take the chair next to him at meetings, she'll ask everyone's opinion on a plan just so she can get Daito's thoughts to see what kind of strategist he is, and while she does observe Team Sinister's training routines and sparring sessions, she pays extra attention when its Daito. She would've liked to work up to polite small talk and conversation but Daito, with the ever keen eye, absolutely called her out on this and to save face, she doubled down. Like they were assigned on a mission and he was doing look out and Kanami was going to ask what she can help with and he, knowing her reputation as a ruthless Queen Bee, was all: "Can you STOP following me everywhere?!"
Kanami: "I-I wasn't!"
Daito: "Yes, you were! I see you all the time! You're always hovering around like an annoying bee!"
Kanami: "I DON'T EVEN KNOW ANYTHING ABOUT YOU. WHY WOULD I CARE ENOUGH TO FOLLOW YOU EVERYWHERE!?"
Daito: "I don't know but QUIT IT."
Kanami, turning around and crossing her arms: "FINE! IF YOU'RE GOING TO BE DELUSIONAL AND WEAR THOSE HIDEOUS GRANNY CHARMS, I'LL HAPPILY LEAVE!"
Daito: "...Granny charms? HEY, DO YOU MEAN MY JADE!?"
And since then, ARGUING AND BACKHANDED INSULTS IS THEIR WAY OF BANTER. Kanami is obviously more passive aggressive with it and Daito is less composed but they do it every meeting. It doesn't help that Inigo and Iker heard them arguing so now they PURPOSELY steal seats so Kanami has to be forced to sit next to Daito. So Kanami being embarassed and not making eye contact with Daito as she takes her seat next to him and Daito just rolling her eyes. When they make suggestions, they have to attack it. Kanami started this when she critiqued one of Daito's plans a little too harshly so now Daito judges hers and she'll continue to judge his as a response which ends up with them arguing, often leading to Octavia or Tonya being all: "Children, can we settle down?" and Daito and Kanami both realize how childish they're acting and they sink back into the seats, sending dirty looks towards the other. But it Daito genuinely has a good idea, Kanami won't ever judge it because she can see the strategy, so she pouts because he was kind of smart for thinking of that and whenever someone disagrees with it, she'd lay down the facts of why its objectively a good idea.
Kanami: "I don't agree with Daito on a lot but as the Queen of the most efficient and superior soldiers in the world, you would be an idiot not to use his strategy! It covers both our offense and our defense. If you want to fail and make another plan, then fine! But my Swarm Riders will be using this one!"
And Daito just kind of going a bit easier on her after that. They're still kind of hostile to each other, exchanging brief insults, but I can see them developing into casual acquaintances. Kanami will notice when HE starts sitting next to her and she will make casual conversation, which he might brush off for a bit until he starts to entertain her by responding to her conversation starters but only if they're interesting. When he offers her snacks, she'd politely decline at first because that feels...too intimate to her (SHE'S NEVER HELD HANDS WITH A BOY THAT WASN'T ONE OF HER BROTHERS, NEVERMIND SHARED A SNACK WITH ONE) but if he keeps offering, she'd feel bad about declining so she'd take a small nibble, which makes Daito look at her wierd but he shrugs it off. IF HE OFFERS ANY HONEY-FLAVORED SNACK, she would patiently wait for him to ask her if she wanted a bite but if he doesn't, she'd tap his shoulder awkwardly and ask if she could have some, and she'd take a normal.
BUT LIKE, YEAH, THEM JUST HAVING THIS AWKARD, TSUNDERE STAND OFF WITH EACH OTHER AND NOT WANTING TO GIVE IN TO EACH OTHER BUT STILL KIND OF ENJOYING BEING NEXT TO EACH OTHER...or tolerating it, at least.
Kanami:["Daito, do you ever think about what we'd be doing if we were...you know, normal?"]
Daito: ["What?"]
Kanami: ["Like...you know, other kids our age are studying for tests right now, setting up school festivals, and other stuff like that. Do you ever think about being a normal teenager instead of...what we are now?"]
Daito: ["No....Do you?"]
Kanami, blushing: ["No! Of course not, I have a Hive to rule! It was just...something that popped into my head."]
and Daito rolls his eyes and shakes his head at her defensiveness but he goes silent because...that's not something he ever really considered before...It's stupid because he'd never want to be normal, but it was...kind of an interesting question.