Bowuigi soulmate AU where humans and Koopa’s have different ways to tell Soulmates, humans have first words their soulmate speaks to them and Koopas tell at first touch.
So Luigi knows they are soulmates first time they meet Bowser and he threatens them and is freaking out at the time because 1) Bowser is trying to kill them and 2) He’s his soulmate!
After Luigi stops freaking out he starts thinking if he should say something, what he should do? He’s not sure how this works especially when 1 knows and the other doesn’t. He’s thinking about telling him but then Bowser kidnaps Peach again and talks about marrying her and Luigi thinks that maybe it’s a non-requited bond that Bowser clearly loves Peach.
So Luigi doesn't tell anyone not even his brother and is just quiet about it.
Bowser has no idea as he has never touched Luigi he always fights Mario and the green one is nearly always hiding or dealing with his minions.
That is until one fight where he decides to use the green one as a hostage... or throw him at Mario and then leave in the chaos... only as soon as he grabs the green one a mark appears on his palm and he just kinda blue screens... Mario knocks him down but also sees the mark and suddenly is freaking out. Luigi has already disappeared just realizing the bond is requited? But that can’t work Bowser loves Peach.
Mario of course talks to Luigi and is shocked he could think his bond was unrequited he’s awesome! and when Luigi starts talking down on himself Mario is instantly like Nope not happening your awesome and you deserve to happy.
Basically wing man Mario who just wants his brother to be happy with his soulmate. No matter who his soulmate is. He is ready to storm the castle to tell Bowser to take his brother on a date.
Bowser freaking out and going into denial while Kamek is torn between so happy Bowser has a soulmate and shocked over who it is (And then after looking into him very approving) Bowser Jr finding out and goign to give shovel talk to Luigi but Luigi ends up going dad mode.
Mario comes in to check on his brother and sees Jr at kitchen table eating snacks and drawing happily. While Luigi is making them hot chocolate.
Bowser Jr: Hello stupid Mario I came here to threaten the green one.
