Alright so the story of To Love Ru is about a boy name Yuuki Rito who gropes a pink-haired alien name Lala who is the princess of Deviluke. After trying to confess his feelings to a girl, Haruna Sairenji, he accidentally confesses to Lala and says to him "Lets get married". From there on Rito tries to get out of the relationship with Lala, but has other things in his way that actually makes him closer to her. The plot does get more of a serious tone towards the end of the anime, but overall it's just a fun anime.
My favorite character in this show is without a doubt Lala. She is one of my all time favorite female characters. I don't know why but I like characters like her. This charismatic, upbeat, joyful personality and always having a positive outlook no matter how bad the situation. Even though Rito accidentally "proposed" to her. Lala loves Rito with all her heart and you can see in the show that she is devoted to him. Speaking of Rito he is a clumsy pervert. Literally think of every way to accidentally cop a feel and he does it. He doesn't like to think of himself as a pervert he just is really clumsy. And yes that is a running gag in this show. I also like that unlike other harem male leads, Rito doesn't want a harem he just gets tangled up into one.
The comedy in my opinion is pretty funny. Even though some people can get irritated with running gags, but I just love them.
Do I think To Love Ru is great. No. In all honesty the story is pretty stupid, but is it funny and entertaining Yes. I think this show is very good, has likable characters, nice music and voice acting. If you don't like ecchi anime then you're going to dislike this show. Overall I say give it a watch.
