Kagami finds out Ladybug's identity.
And it just so happens to be her girlfriend.
Spotless contains examples of:
- Adaptational Sexuality: In canon, Marinette and Kagami are both rivals for Adrien's affections. Here it eventually led to the two of them getting together instead.
- Battle Couple: When Master Fu finds out that Kagami knows Marinette's secret identity, he meets her in person and decides to give her the Dragon Miraculous full-time.
- Character Tic: Even though she is no longer pursuing Adrien, Marinette still tends to stutter around him.
- Secret Keeper: Kagami finds out that Marinette is Ladybug when she detransforms in-front of her, not noticing Kagami in her room when she returned from a battle. Naturally, Kagami is quick to fret and worry over Marinette being in danger.
- Sorry, I'm Gay: When Ladybug gets sick of Chat's incessant flirting, she tells him that she has a girlfriend and that he should quit while he's ahead.