Night Calls is an adults-only (R18) 19-page M/M yaoi comic about a knight who summons a demon in an attempt to negotiate for a dead man's soul. Instead, he gets the chaos lord himself, who is certainly willing to go through with the contract under specific conditions. Though, when he asked for the knight to submit, the chaos lord didn't think the knight would be quite this willing in the end.
This is the free low res version, a high res version can be bought on http://maccastar.itch.io