Oh! That's the member of Minato-kun's team, SEES. They fight badguys, and stuff! Koro-chan is like you, I think.

[ He can see you properly, Ammy, considering the fact that he is connected to a Goddess as well. ]

Koromaru has the ability to summon a Persona! It's basically a part of his psyche given form that he wields to help fight badguys. You guys would get along really well, I bet.