in normal manga
a friend is establish if they have lunch, going home, confess though about each other, solve misunderstanding, birthday, summer break, new year, valentine event
but in iris zero
Tooru was just solving problems tool in the start thanks to one iris and then people start to create problem for him to solve thanks to certain someone useless
you like someone cause they got dark past and kind enough to solve your problems
now i wish it just curious, got to see that again