Headcannon number 1- Ishimaru tends to sleep in Mondo's T-shirts but denies the fact of doing so.
Headcannon number 2- Ishimaru holds a very precise schedule for every morning and gets quite angry at Mondo for not following it as well.
Headcannon number 3- Ishimaru has a rule of no electronics before bed but Mondo usually disobeys Ishimaru leaving his pissed.
Headcannon number 4- Sometimes Mondo will build pillow forts just for the two if them to cuddle in.
Sorry for not having a lot of them- I have some more for different places but uh- yeah-