16-year-old super-studier Nagi Umino, second-year student at the Megurogawa Academy high school, was switched at birth. On his way to a dinner to meet his birth parents, he accidentally meets the brash, outspoken, Erika Amano, who is determined to make Nagi her fake boyfriend as she never wants to actually marry. But once Nagi makes it to dinner, he finds his parents have decided to resolve the hospital switch by conveniently having him marry the daughter his birth parents raised...who turns out to be none other than Erika herself!
A Couple of Cuckoos (Season 2)

Who Was Umino-kun's First Love? (Episode 1) 7.0
Writer: Masakazu Hishida
Air date: 2025-07-08
Runtime: 24 min
Overview: Hiro moves in with Nagi, Sachi and Erika. Friction arises, but they're reminded of what happiness might mean.

Onii Confessed to You, Didn't He? (Episode 2) 7.0
Writer: Masakazu Hishida
Air date: 2025-07-15
Runtime: 24 min
Overview: Hiro is kidnapped and Nagi immediately sets out to save her.

That, but Times a Hundred (Episode 3) 7.0
Air date: 2025-07-22
Runtime: 24 min
Overview: Nagi is suddenly hit with the truth about Ai’s real objective.

I See You're All Together (Episode 4) 6.5
Air date: 2025-07-29
Runtime: 24 min
Overview: Hiro is preparing for a festival that's about to be held at her shrine.

It's My Life, Too! (Episode 5) 7.0
Air date: 2025-08-05
Runtime: 24 min
Overview: The world now knows the face of singer Mochizuki Ai, who created the song “Arc Fault.”

There's No Way I Can Be Normal!! (Episode 6) 8.3
Air date: 2025-08-12
Runtime: 24 min
Overview: Nagi and Erika are trapped in a hotel room by her mother, who seems to be playing with them.

It's Ours to Build! (Episode 7) 7.0
Air date: 2025-08-19
Runtime: 24 min

No Such Thing as a Meaningless Kiss (Episode 8) 7.0
Air date: 2025-08-26
Runtime: 24 min

The Real Enemy is Sachi-chan!! (Episode 9) 7.5
Air date: 2025-09-02
Runtime: 24 min

I Know, Nagi-kun! Let's Take Pictures for Memory's Sake! (Episode 10) 7.7
Air date: 2025-09-09
Runtime: 24 min

I Found Him Attractive for the First Time (Episode 11) 8.0
Air date: 2025-09-16
Runtime: 24 min

Thank You for Falling in Love with Me (Episode 12) 8.0
Air date: 2025-09-23
Runtime: 24 min
