Complex sentence: In the anime, he destroys Presea's house with his monsters, and essentially causes her death; later, he confronts the Knights again (their first encounter in the manga), but Umi slaps him for using his friends and causing them pain.
Split into simpler sentences: In the anime he destroys Presea's house with his monsters, and essentially causes her death. Later, he confronts the Knights again (their first encounter in the manga), but Umi slaps him for using his friends and causing them pain.