I'm a bit (too much) late but, does this works if i have used the gakuren costume before that Tocchan shows the photo?
I'm also really late since I haven't checked Itchi in ages XD It's been a bit since I played the game but I believe it would still work since it's just requirement triggers. Although, you've probably already discovered this yourself since it has been a year since you posted this according to the time stamp, lol.