Hello! Thank you for asking. As long as you feel there would be no ambiguity in who the group name is meant to refer to for anybody else potentially offering or requesting that fandom, it is fine to nominate the group name and it will be approved. (Mods cannot enforce which characters do or do not "count" as belonging to a group that doesn't specify character names, so if you feel there could be ambiguity present it would be best to list out the characters.)