AKA things my silly little brain came up with when I'm half asleep that may or may not make sense.
Steve understands technology a bit more than Tony gives him credit for. There have probably been times where Tony is going super in depth on how to fix a technological issue, only for Steve to waltz up, unplug it, and plug it back in again, and it works.
Steve drags Tony on dates at least once a month, and those dates are stupid and cheesy and Tony makes fun of him for it all the time except he secretly loves it. Like, laying in bed, kicking his feet after the date amount of love.
Tony obviously pampers the HELL outta Steve. Like... a LOT. But Steve pampers Tony right back, in his own way. Massages, flowers, drawings, anything he can give Tony that means something.
In his very limited spare time, Steve sits on the couch in Tony's workshop and watches Tony work. He sketches him in a little sketchbook that Tony bought him. He sneaks those sketches into Tony's work case, in between his papers for Stark Industries.
Tony keeps those sketches in his workshop when he finds them.
Tony's love language is touch. He tries to pretend it isn't, but it totally is. It shows in the way he melts into Steve's arms after a particularly rough day. It shows in the way he plays with Steve's hair during Forced Team Bonding Movie Night.
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Bucky has nightmares. Of course he does. But people don't seem to realize that Steve has them too. When Steve wakes up from a nightmare, Bucky makes him a warm drink, sitting with him until he finishes it or until he falls asleep. Just like he did when they were kids.
The arm that Bucky got from HYDRA tended to pinch in weird places and was very painful to use. When Steve found this out, he went straight to Tony. In the end, Tony got to ditch team bonding time for a month. Steve got Bucky a new arm.
At first, Bucky refused to touch Steve with his metal arm. He didn't believe that something that had done so much harm could be gentle when it was most important. One day, Steve took Bucky's hand, and just held it. Bucky didn't let go until he fell asleep.
Steve plays with Bucky's hair constantly.
Bucky put eyeliner on Steve once. He didn't notice until Tony burst out laughing in the middle of a mission debrief.
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Tony keeps his distance for a long time. It's Bucky who comes to him, explaining that his arm is malfunctioning. He says it hinders him during missions, and that it was a liability. Tony fixed it and insisted on bi-weekly check-ins. It's during one of these check-ins, when Bucky finally lets Tony remove the arm, that Tony begins to fall for him.
Tony is super jealous of Bucky's friendship with Steve at first. When someone brings up the idea of Steve and Bucky as a couple, Bucky doesn't stop laughing for at least five minutes. The jealousy faded after that.
Tony uses JARVIS/FRIDAY to mess with Bucky all the time. Whether it's calling him to the workshop just to remind Bucky that he loved him, or if it was programming the AI to only refer to Bucky as "Terminator" or "Sugarplum" or "Rapunzel".
Bucky started wearing his hair in a half-pony when it got too long. Tony was exceptionally normal about this (he was not).
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Tony biggest turn-on is competence. The second that he met Bruce on the helicarrier, he was gone for him.
Bruce keeps the mini-fridge in the lab stocked because he knows Tony won't bother to leave the lab to get food when he's in The Zone (TM).
Tony has tried to find a cure for Bruce's gamma radiation. He gets frustrated whenever he works on it. Bruce makes him go to bed whenever he catches Tony working on it.
Bruce mostly sleeps in Tony's penthouse, but Tony makes sure that cleaners tend to Bruce's floor at least once a week anyways. He knows Bruce isn't a huge fan of heights.
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Anyways ik most of these aren't realistic but they're just silly little things my squirrel brain came up with when I'm half asleep!!
Also hi! Idk how Tumblr works!! I'm gonna be posting mostly about marvel, mainly ships such as the above, and I'd love to find some friends! Anyways time to go pass out in bed k bye <3