Ataru Moroboshi is the male protagonist in Urusei Yatsura. He is the most lecherous teenager in the universe.(Revealed in Always My Darling). At times he shows extreme intelligence while running away from Lum and he possesses the endurance abilities of a cockroach and regenerative abilities of a lizard. Most of the times you will see him as a lecherous loser but look more closer and you'll see its an act. He had helped a ugly caterpillar grow into a beautiful fairy and helped a Amefurashi cursed girl get rid of her curse. Also one of the most favourite episodes of many people is episode 157 where Ataru helps a ghost girl named Nozomi rest in peace by dating her as Nozomi had feelings for Ataru but couldn't reveal it to him at the time she was alive because she had spent all her years in a hospital bed-ridden.
In the English version of anime, he was voiced by Michael Sinterniklaass for Episodes 1-2, AnimEigo, Steve Rassin for Movies 1, 3-6 and Vinnie Penna for Movie 2 who is best known voiced as Joey Wheeler and Michelangelo.
He is the most lecherous being in the universe with a funny personality, and has no intrest in studies.Whenever he sees or hears a pretty girl he immediately pounces upon them and asks for their address and telephone number.Everyone living in Tomobiki calls/knows him as a pervert (Even Shutaro Mendou is no match for him in pervertness) No matter how much Ataru gets beatings by women he keeps on coming again and again which shows he sub-consciously enjoys getting abused by women. At first glance you might think of him to be an idiot but make no mistake because Ataru is expert in escaping from others often using intelligent ideas.One gag running through the series is nobody has respect and love for him(Except Lum) even his own mother keeps wishing she should never had him and his father wishes they had a girl instead of a boy which shows that his parents don't care much about him.The only one who loves Ataru truly from her heart is Lum.
Ataru constantly tries to ignore Lum but it is proven many times that Ataru cares about her and she is the one he actually loves. Deep down he has a heart of gold and he is very noble but ,alas, nobody seems to realise it except Lum (which might be the reason why she hopelessly fell in love with Ataru).
- Lum - Ataru met Lum when he was randomly selected by a computer to represent mankind in a game of tag with the fate of the Earth on the line (Lum herself represented the Oni race). When it looked like Ataru would fail, Shinobu (his girlfriend at the time) promised to marry him if he won. Determined to do "the stuff that married people do", he succeeded in catching Lum and then loudly declared "Now I can get married!!" However, Lum mistook this as a proposal to herself and the two were immediately engaged. In the beginning he is cold-hearted towards her and saw her as a nuisance preventing him from girl hunting, but by the time of the story "A Night Alone!!" (夜を二人で!! , Yoru wo Futari de!!) (Vol. 18) he was completely okay with sharing a bed with her. He is also shown to be quite jealous if another guy gets to close to Lum (ex: Rei, Shuutaro, Shingo, the Dolphin, etc). In the story "The Gloves of Love and War" (愛と闘魂のグローブ, Ai to Tokon no Gurōbu) (Vol. 21), in which he accidentally puts on boxing gloves that force him to grab and punch anyone who gets close enough to him, he continuously puts his own face in front of Lum's each time she gets too close, punching himself instead. This is just one of many instances when Ataru does everything he can to protect Lum from physical harm. Near the end of the series, in the story introducing Inaba, he decides to protect the future where he and Lum get married. In the final story they have another game of tag, this time with the Earth's memory of Lum and everything that has happened since her arrival on the line. Lum will let him win if he just says "I love you", but he refuses and tries to catch her himself. However, in the end, he indirectly says "I'll love you forever" when Lum sees that he had kept something of hers (her old horns). She allows him to catch her and continues to live on Earth with him. In the last panel of the series, Lum says that one day she'll make him actually say it, to which Ataru responds "Only on my deathbed".