Ren Arisugawa is a hugely popular male celebrity—except she’s actually a girl. She’s kept her true gender a secret, even from her cousin [Kyouhei](https://anilist.co/character/380638/), though he has always been important to her. She’s self-conscious about her femininity.

A secret that could shake the entire entertainment industry— This sweet and innocent rom-com is a long-time bestseller! Kyouhei's one and only claim to fame? Being cousins with Ren Arisugawa, an ultra-popular male idol. The two haven’t seen each other since they were kids, but out of the blue, Ren suddenly shows up to crash at Kyouhei’s rundown apartment. But when Kyouhei playfully tries to sneak a peek while Ren’s changing, he makes a shocking discovery! Ren is actually a girl in disguise! Now holding a scandalous secret that could rock the showbiz world, Kyohei finds himself forced into becoming Ren’s personal assistant to keep up the act…! Caught in a world of secrets and scandals, can the two keep their forbidden relationship under wraps in the wild world of showbiz?
 
(Source: Official Site)
 
Note: Episode 1 received an advanced distribution on AnimeFesta on December 12th, 2025. The start date reflects the start of the regular series broadcasting.

"D-...! Don't tell her. I'll do anything..." The popular talent, Ren Arisugawa... is actually a girl! This situation, I'll use it to my advantage... okay?
 
(Source: Coolmic)
 
Volume 1: Honto wa Ecchi na Onnanoko. (ホントはえっちな女の子。) 
Volume 2: Honto wa Ecchi na Onnanoko.: Sweet Scandal-hen (ホントはえっちな女の子。～スイートスキャンダル編) 
Volume 3: Honto wa Ecchi na Onnanoko.: Gossip Night-hen (ホントはえっちな女の子。～ゴシップナイト編) 
Volume 4: Honto wa Ecchi na Onnanoko.: Melty Scoop-hen (ホントはえっちな女の子。～メルティスクープ編)
 
Notes: 
- Includes 4 extra chapters. 
- Originally serialized as a web manga under the title Arisugawa Ren tte Honto wa Onna nanda yo ne. (有栖川煉ってホントは女なんだよね。). 
- Simultaneously released in long-strip and traditional formats, with 171 episodes and 57 chapters respectively. 
- The first 6 chapters were previously given a tankoubon release as Ore dake ga Shitteru Aitsu no Himitsu (俺だけが知ってるアイツの秘密) under the publishing label Comic Gloss.