AOT: Nexus The Titan Hero (Harem X Male Reader)

(Y/N): "NEXUS!!!!!!!!!!!!!!!!!!!!!!"

(Y/N) (L/N) AKA Ultraman Nexus is the hero of galaxy and he was being sent by Ultraman King for the mission to rescue the mankind from the creatures were called is...Titans and they were same height as Ultramen. But the mission is eliminate the Titans and they both are threat of mankind in the future for themselves and then (Y/N) must save the mankind for the future of the different world...so (Y/N) went there and made it to the different dimension and universe for himself...(Y/N) seen these creatures are taken over the mankind's world and (Y/N) will eliminate them and all every titans by himself and he cannot let these titans destroy the mankind by themselves.

What will he do if he meet Titan Shifter? Shall he destroyed them? Or fighting them because he doesn't trust anybody else who were backstabbed at him.