Soooo... I'm not very happy right now because shit happened and my cellphone fucking fell from the window of my apartment, so I decided to write some of my headcannons for my boys to cheer me up.
I love the idea of Steve just being that person that jokes about everything because he genuinely want people around him to smile, even when things are horrible.
Billy is a little bit of a jealous tipe and he makes that very clear when they started to get close, so Steve just started to explain all the things that might get him like that (some of these are just some dumb stuff a five year old could have figured out, but he doesn't want to leave any doubts) eventually they move past that.
They are verse. They first time was pretty awkward because Steve had no idea what to do (they don't just give you a manual of gay sex in school) and having him to admit it just made Billy laugh so much because it was so cute.
He is passive that time so Steve could have a more familiar role.
Billy was surprised when he first listened to Steve music. Turns out the classical boy actually liked some good shit.
Once they were both really drunk and tried to make some rap about nothing especially. Steve drunken beatbox was the best thing.
Once Billy started the "path of being a better person" or something like that, he started to get really worried about having a relapse and it was very difficult for him to convince himself that he wasn't that kind of person.
Although Steve was a really easygoing person, you don't want to ever get on his bad side. Billy wisely don't push too far, but you can't say the same thing about some other people...
They like to watch movies together, but always pick the worst so they can mock it and laugh about the errors. Sometimes they simply fall asleep in the end.
The 'love you's start late in their relationship. Steve was afraid of heartbreaking and Billy was confused because he never loved someone and it was terrifying. But when they start they grow pretty normal, like one phase for: "good bye", "it's ok", "sorry", "see you later", "please" and "you are freaking beautiful" at the same time.