Like The Ropers is to Three's Company, Konami spun-off several Castlevania-related games in the hopes that the familiar backgrounds, characters, and stories would compel more people to play the real Castlevania games.

Vs. Castlevania
Released: 1987
System: Coin-Op

In the late 1980s, Nintendo made special arrangements with a few licensed developers to release two-player versions of popular games into the arcade. Konami created a two-player Vs. Castlevania, which is nothing more than a more difficult Castlevania I with alternating players.

Konami World
Released: 1988
System: Famicom (The Japanese version of the NES)

Monsters and machines have trapped Konami's greatest heroes. You, Konami Man, must save them all by venturing into Konami's greatest home games. And, in a level vaguely reminiscent of Castlevania I, you get a chance to save Simon Belmont!

Konami World appeared only on Famicom in Japan. It's a terribly difficult game; monsters attack fast and continues don't save your game play unless you've finished an entire title level. At least hearts give you health - small hearts give a couple boxes, big hearts give more. When you die, Konami Man transforms into Konami Girl, giving you another life.

Castlevania II: Simon's Quest
Released: 1988
System: Handheld LCD Game

Well, at the height of NES Castlevania popularity, Tiger Electronics released a Castlevania II: Simon's Quest handheld. You, Simon, walk right in, whipping anything that comes close. Someone creeps up behind you? Turn around and whip 'em. As in the real Simon's Quest, the enemies become stronger when night falls. You have a whip, of course. You also have a limited supply of daggers that kill enemies pretty quickly. Occasionally, a ball floats across the screen that replenishes your life and dagger supply. And when you come to water, you jump from block to block. (Two buttons control jumping; one jumps straight up, the other up and forward.)

However fun to play, the game is very hard to find today. Most handhelds depend on license popularity. So, Castlevania II, the handheld, lasted only as long as Castlevania II, the NES game, remained popular.

Kid Dracula
Demon Castle Special: Dracula-kun (Kid Dracula) in Japan
Released: 1993
System: Famicom (The Japanese version of the NES)

Remember Muppet Babies? The point of that show was "things made small become cute." This is the reasoning behind Kid Dracula. Poor Drac has been demonized so well by the Castlevania series that he needed an image upgrade. Never mind the fact that he still has to drink people's blood to survive.

So, as small, cute Drac, you run around, hurling fireballs at smaller versions of previous Castlevania monsters - knights, Frankensteins, and so on. Later in the game, you can change into a bat. And that's pretty much it.

Kid Dracula appeared on Famicom first, but was then released to US Game Boys (sort of a small, cute NES) with different levels and weapons and the ability to change to a bat from the start.