Kaim is a male demon from Devilman who is in love with Sirene. He is a quad demon with 2 spiked horn tusks that protruding from his shoulders and an extendable tail that he can grab things with (like his own head).
In both the anime/manga he comes to help Sirene fight Akira Fudo(Devilman). With Sirene on the verge of death, he suggests that in order for her to defeat Devilman, they would have to merge. He professes his love for her and kills himself by yanking off his head with his tail so that Sirene would keep her consciousness when they merge. The resulting appearance of the merged demon had Kaim's body with Sirene's upper torso coming from where his head once was creating a centaur-like creature. The newly merged demon zapped Devilman with energy then skewered him through the abdomen with one of it's tusk. In a panic, Devilman quickly flew off the spike and landed by a river and reverted back to Akira, rendering him unconscious. The new Demon felt victorious after the defeat of Devilman but shortly after, it died in a statue-like form from Sirene's severe wounds.Sirene taking an ice water shower(but she is basically nude anyway so it don't make much difference if she's in the shower or not) and later brings her talons back to her after the battle at the glacier in OAV 1. He is seen with her during the rest of the OAV's and it is revealed that Amon's soul is inside Kaim because of Psycho Jenny (but this goes against the Amon: The Apocalypse of Devilman)