Sylvia

Sylvia is a major antagonist in KonoSuba, specifically appearing in the Legend of Crimson movie and the corresponding light novel/season 3 arcs.

She is a chimera created by the Demon King's army.

Personality-wise, Sylvia is extremely arrogant, sadistic, and prideful about her strength and beauty. She loves showing off, tends to monologue dramatically, and gets genuinely upset when people don't acknowledge how impressive she is. Despite her over-the-top villain attitude, she's considered one of the more competent and dangerous generals of the Demon King.

Her most memorable (and infamous) trait among fans is her very revealing outfit and the way the story handles her... unique body proportions and certain "interactions" later in her arc.