「けいおん！」

The plural of anime is ANIME, not ANIMES.

Just to put this out, but the plural for anime is ‘anime’, not ‘animes’! It irks me to no end to see people using ‘animes’ and ‘mangas’ as plural forms -_-

‘Anime’ is the romaji for アニメ, which is a Japanese word. The Japanese do not tack on ‘s’ on the end to signify more than one.

It’s like saying, “There are a lot of sheeps at the farm” instead of “There are a lot of sheep at the farm”. Fairly obvious why that’s wrong, lol.

It may be just ignorance, but anyone who has actually studied Japanese at school/college/university, would know that the Japanese do not have plural forms (there are some rare exceptions though).

“I have seen many anime” is CORRECT. 

“I have seen many animes” is INCORRECT.