When the hydrangeas are falling

From the outside, Yuuta's relationship with girlfriend Natsuha looks perfectly fine, he's devoted, the relationship looks normal from the outside, and he has no reason to suspect anything. But Natsuha is keeping a secret, a separate relationship happening right under his nose that she finds far more fulfilling than what she has with him. That tension, someone being completely unaware while their partner is emotionally and physically somewhere else entirely, is the core of this one-episode ONA from T-Rex, based on the manga of the same name. It's a short runtime, so it moves fast, but it leans into the emotional messiness rather than glossing over it. The character designs are expressive and the animation holds up, which helps sell the mood. The story doesn't try to make you comfortable with what's happening, there's a real sense of unease underneath the surface. If you've watched something like Kimi ga Yobu or Toriko no Kusari and appreciated how those handle complicated relationship dynamics with some actual weight behind them, this hits a similar note. It's not trying to be a grand romantic drama, but for a single episode it does more character work than you might expect from the setup. Worth a look if infidelity-focused narratives with a grounded high school setting are your thing.