Vegeta is more of a rival than a nemesis.
My first thought was Frieza, but there's definitely a strong case to be made for Dr. Gero. Gero held a death-grudge against Goku ever since he took down the Red Ribbon Army as a kid, and worked tirelessly creating androids for the sole purpose of killing Goku for, what? Twenty? Thirty years? That's some grudge.
Yeah, I think I'd have to go with Gero.
Plus, isn't ecchi mean really risque clothing but no nipples are shown?
...no. I don't know where you got that idea from.
Ecchi is a genre, is basically means erotic fantasy. An anime is considered "Ecchi" when it has sexual themes or undertones, here's a list of Ecchi anime. Ecchi shows range from things like Astarotte's Toy to Queen's Blade and Kiss x Sis. Look it up on Wikipedia if you like.
It's anime between innocent anime and full-on hentai. Smut on the other hand is just another word for porn, generally used in a more negative way than the word porn or pornography.
@dinnahoag: Moving this to off-topic since it isn't about anime or manga.
I've always loved superhero cartoons, but I haven't been into actual comics for very long, jumped in during the New 52 stuff. My favourite comics right now are probably Justice League, Ultimate Spider-Man and Spider-Men. I'm actually behind on Justice League and a bunch of other DC comics I read, so I have some catching up to do.
@nickzambuto: Sorry, we aren't that kind of site. Having lots of pornographic images on the site actually got us blacklisted by Google Image search and as a result cut our incoming traffic in half, so having that sort of content actually hurt the site considerably.
There are thousands of hentai boards out there, so if that's what interests you, pick one of those. If not, stick around here and feel free to discuss anime, manga, cosplay, figures, Japanese culture and even unrelated subjects in the off-topic board, or help fill in our awesome wiki. Hentai can be discussed and added to our wiki, but we don't allow any images featuring sexual content.