Laughed my self silly over my hc about Tobirama having an insanely low tolerance to poisons and it offends him so of course he throws himself into finding a way to make sure it never becomes a problem again so he purposely doses himself and nearly gives Hashirama an aneurism each time because
"What the hell are you doing spit that out!!"
And Tobirama simply glares with the very much poisonous mushroom in his mouth before Hashirama lunges
Hashirama is shrieking as he tackles Tobirama and tries to pry Tobirama’s mouth open to snatch the mushroom away and Tobirama curls his legs, knees to his chest and plants his feet on Hashirama's chest and he *kicks* and Hashirama goes flying and Tobirama takes that moment to swallow the mushroom whole.
And that's the moment where the cain instinct activates.
Hashirama comes running back and punches Tobirama in the stomach in an attempt to get him to throw it up but Tobirama stubbornly keeps his naughty poisonous snack and retaliates with a round house kick of his own.
The room soon becomes a battle ground- the table is crushed under Tobiramas body as he's thrown into it, the chair smashed as he hefts it up and smashes it onto Hashiramas head, the walls are littered with holes from punches and kicks and the occasional body being thrown into it.
The window is shattered when Tobirama tries to make a break for it by escaping through it before Hashirama hauls him back into the room by grabbing onto the back of his shirt
The only reason the fighting ends is because the mushroom eventually takes affect and it makes Tobirama double over to vomit and Hashirama sighs and gently rubs his back.
"I told you to spit it out."
"I would have been fine."
"You can't be eating poison on your own! At least have someone with you!"
"I did!"
"A CLONE DOESN'T COUNT!"
"Brother, shut up and restart my heart, I'm going into cardiac arrest."