
Bubble Bobble, by design, is meant to be played together by a dude and a lady. I'm absolutely certain of this, but I can't explain why. During the half-dozen or so times I've played through Bubble Bobble in my lifetime, I've always enjoyed it more when playing it with a female friend. I've tried playing through it with male friends, and it always ended badly. Something about it just felt weird and wrong. I even played it once with my brother, and that's not something I think I should even talk about.
I have a few friends who have reported similar findings in their own experience. Girls enjoy playing it more with guys. Guys think it's more fun with girls. I don't know what any of this means, but if ever there was such a thing as a "date game," Bubble Bobble is it.

That's something you only have to worry about in two-player mode, though. Bubble Bobble makes for a great single-player experience as well. The plot's nothing original or special -- it's your average story about dinosaurs who trap enemies in bubbles and pop them for bonus fruit. Unlike other games in the crowded bubble-spitting dinosaur genre, though, Bubble Bobble keeps it simple with fast, arcadey gameplay. Blow bubbles. Pop all the enemies. Go to the next level. At the end, you shoot lightning at an evil drunk. Oops, spoilers.
The level layouts and enemy types will gradually ramp up in difficulty throughout the game's 100 levels, though, keeping it a fairly decent challenge throughout. It gets kind of crazy by the end, actually. The first few levels are simple jump-and-pop exercises, but by level 90 or so, you'll be bouncing off bubbles guided by invisible air currents in order to get a shot at seemingly unreachable enemies trapped inside walls.
The thing that strikes me most about Bubble Bobble is how insanely complex it is underneath its cute exterior. You wouldn't expect such a saccharine-looking game to feature a deep and subtle point system, for one, and then there's all the seemingly random drops of rare items that are actually triggered by behind-the-scenes math that keeps constant tabs on distance traveled, jumps performed, and the number and types of bubbles that are popped, among other things. The arcade version has a separate counter and special item that triggers whenever someone enters the name "SEX" on the high score table, for crying out loud. You'll see new and weird things happen just about every time you play, and as random as any of it may seem, all of it can be duplicated by keeping track of the game's internal math.

Bubble Bobble's an amazing game on many levels. It's easy enough (at first) for players of any skill level to enjoy, but if you ever attempt high-level play, you'll find a massive amount of depth and challenge for a game of its era. The NES version lacks some of the complexity of the original arcade release, but it's an incredibly fun game regardless, and it's one of the best purchases you can make on the Virtual Console today.
I still can't explain why it's better with a second player of the opposite sex, though. Maybe the game's internal math detects the sex of each player and automatically configures gameplay to be more fun, I don't know.
I was hoping to find a video of an arcade playthrough, but it doesn't look like there's any on YouTube. Anyone got a link to one? Here's some footage of the NES version instead.