Love Smash! 5: Tennis Robo no Hanran
This sequel brings the total character count to 12, including two secret characters, each with their own stats and special moves. There are four different courts, all of them highly-unorthodox. There is a specific focus on the female characters, as each has multiple unlockable outfits and full CG ending movies. There is also a "photo gallery" that includes images of each character, and a model viewer where each character's animations can be viewed from any angle.
The game was re-released in 2005 as Love Smash! 5.1 as part of the Simple 2000 Ultimate series. This version features updated character models and minor gameplay tweaks, but is otherwise identical.