OMG with the way TG:re is heading, I sincerely hope that Ishida Sui will reveal Tatara’s backstory. I really hope that he becomes an important character (and gets more screen time) since I would love to see the reason why he joined Aogiri (plus Aogiri’s goals-“To smoke out a liar”? right Tatara-san~)
Besides, if he doesn’t become an important character, what’s the point of alluding to his past in TG chapter 141 and expanding on it in the anime? Plus Tatara even got a cameo in one of the ending cards (alongside Suzuya and Rize) who are important characters so I’m betting that he’ll at least get more focus in TG:re…(of course I could be wrong, I dunno).
If his past ever comes up in TG:re, I’ll probably start crying both in happiness and the (probable) sadness of it :) Ishida you love making all your characters tragic, don’t you?