Love his silly expression.

Also, apparently "Pain Room" (痛部屋) is the term for the room that one has filled with merchandise (mostly anime/game-related and such). Dunno if there's an equivalent in English. (Well, I suppose I could use "dungeon" but I'm just gonna leave it as is)

A related tag is itasha, which is for cars (and other vehicles) plastered with anime/manga characters. The bag Len is carrying is also a Ita-bag (bag plastered with badges and other items depicting anime characters), which from my understanding is popular apparel to female otaku. Actually wouldn't be surprised if this was supposed to be a depiction of a female otaku cosplaying as Len and showing off her Len room and bag.