Parasyte

Parasyte (kiseiju) meaning "parasitic beasts" is an anime based off of the parasyte manga written and illustrated by Hitoshi Iwaaki. Two live action films are adapting this anime and manga into films. Parasyte revolves around a 17 year old teenager named Shinichi Izumi who lives a normal student life. His life suddenly changes when in the middle of the night a bug crawls into his room.

Later we find out that it's no ordinary bug! 

This anime is really exciting and I would recommend it to anyone who enjoys adventure and the learning experience that comes with the progression of the anime.