Here's a link to a good online name generator. If you're going to be a writer, you need to learn how to invent names.
clawdia
The Monster Slam The Good Bye The Twisted Neck The Knocker
Players on Moshi Monsters give their Moshi Monster a name when they first adopt it. Most monsters are only given one name and do not have a "last name". However, you could consider their last name to be the name of their monster species or type. So the monster's last names would be Luvli, Furi, Katsuma, Poppet, Zommer, or Diavlo.
Elmo's last name is Monster, they(the people that make Sesame Street) have mentioned this numerous times throughout the series. Many of the monsters last names are Monster.
Here's a good link listing the top 1,000 American last names!
Purrsephone doesn't have a last name, her name is just Purrsephonie.
ifrit,pyro,cyndaquil, roy mustang (lol)
If you are looking for American graphic novels, you can try the Walking Dead, Watchmen, Y: The Last Man, and Batman: The Killing Joke. Some good foreign graphic novels are Akira, Monster, Sanctuary, and Persepolis.
cordoba
Beaverhausen
Any last name that you like is a good one! Your characters are yours - you don't have to ask some anonymous person on the internet about them.Here's a good LINK to a list of last names you might like.
Any Korean last names. Such as; Kim, Song, Lee, Choi, Yim, etc.