Killing Bites

Humans turning into bug/animal-like creatures. 

Both shows have Animal skills obtained by surgery, brutal fights and a storyteller explaining this abilities during the fight. But KB has hot girls while Terra Formars has cockroaches 

-Both series are focused on humans being able to half transform and use the abilities of other life forms through genetic ingeneering. In Terra Formars it's more varied, having invertebrate, vertebrate, plant, e.t.c based transformations, whilst in Killing Bites it's mainly mammals, and some reptiles. -Both animes are quite violent and bloody. -Both offer decent fights involving the powers and characteristic of the animals the character transforms into e.g the strenght of an ant at human scale or the speed of a cheetah. 

Both have excessive blood and violence, and have essentially the same power system with humans gaining the power of bugs/animals. 

Both of these are action ecchi series with an interesting power system, filled with unique abilities and cruel fights. Both have a lot of unnecessary fanservice and a scene of lesbian sex involving the main character (what a coincidence). Killing Bites is doubling down on ecchi and takes its plot less seriously. It looks fine (If you can ignore a few ugly CG characters), but Gleipnir's style excels it dramatically. 

Both involve people that were experimented upon and now must fight (and adapt to their new powers / experience personality changes associated with gaining the new powers) 

Both are about a game of killing between anthropomorphic girls and guys. Behind both games there are people who bet on the winner. Both are very bloody and similar in the drawings.