Illumise is a Bug Pokémon introduced in Generation 3. While it doesn't evolve into or from any other Pokémon and has no alternate forms, it's clearly related to Volbeat. It's a female-only Pokémon, with Volbeat being the male counterpart, and Illumise is capable of birthing both.
All canon Pokémon are available in Tropes vs. Women in Pokémon Training, including Illumise.
In the game's Nintendo Switch remake, Illumise evolves from a Baby Pokémon, Lightug, at Level 10 (if female, of course). Because of this, Illumise no longer produces Volbeat eggs, and Tropes vs. Women requires no Incense to breed this Pokémon. Illumise also has a regional form with is Bug/Electric; its abilities change to Lightning Rod, Tinted Lens, and Severe Weather. Its stats?