Colonel Bagel

A high-level-learning AI that Rein developed. A low-key master who loves country music from Colorado, where he was born and raised. He's a cat-like... something... that has tons of 'back-story' given to him, with an eye-patch that seals the power of his evil eye-- when he removes it, his Nidhogg blood awakens.

He's incredibly highly skilled, but these days he's just been Tsukiko's playmate, causing him to put himself down as a babysitter AI.