He shouldn't.

As a priest, it is his duty to guide his flock, to set an example, to protect them. Tatsumi can't help but step back, looking at the hand outstretched in front of him.

He really shouldn't.

This is for the greater good, an asset to assist him— that's what Tatsumi is repeating in his head, as his hand set over the one in front of him. Those horns, that tail flicking about, the wings that looked like bones...

He gives into temptation, sealing the deal with this demon.