^ It's also a common nickname / there are most likely thousands of other girls with that name, including MANY in other groups or fandoms I'm a part of. And I'm not a big MM fan, sorry I guess.
I know only two idol Eris, both has retired already (the other one is my 9th gen (AKB48 of course) first love, Takamatsu Eri). It's not very common name.
^ ^ The point I was trying to make is I've seen a lot of girls named Eri or nicknamed Eri, and as such just saying "Eri" wasn't something that stuck Eri Kamei in particular, to the front of my mind.
Yeah... I only follow H!P (I'm not interested in AKB48) so there's only one person I could have been taking about, MM:OG's Eri. Eri's not really a safe nickname to use for either Erina since it can get pretty confusing.