Hm...
The 4-Koma and the anime suggest it is col. Fan translations all over go with col. There are official translations that are worse off than fan translations. I think that is the case with this one. 

I can't actually confirm it though. コル is what it is, and that is ko and ru. So in a way Col and Coll would both work.

Anyway, RPG wasn't working so I couldn't get a post in, will try get a post in soon, if I can.