Forbidden Love

When a princess crash-lands on a college student's roof and gets brainwashed into thinking she's his little sister, that's somehow only the beginning of the weirdness. That's the setup for Imouto de Ikou!, a two-episode OVA from 2003 that wraps its adult content in a genuinely strange sci-fi premise. Princess Mayuka was sent to Earth on a mission — recharge something called the Ultimate Weapon — but things go sideways fast when her research subject, a guy named Yoshizumi, turns her own gun on her and scrambles her memory. Now she thinks she's family. What follows blends the fish-out-of-water comedy of an alien learning human customs with the kind of erotic content you'd expect from the genre, plus a dose of dramatic stakes involving the weapon she came here to activate. It's a weird mix, but it holds together better than it has any right to. If you've watched Imouto Paradise! and want something with a bit more plot scaffolding underneath the explicit material, this scratches that itch. Fans of older titles like Jungle de Ikou! will recognize the same energy — goofy sci-fi logic played mostly straight, wrapped around content that definitely isn't for everyone. The two-episode runtime keeps it tight, so there's no filler dragging it out. It's not trying to be profound. It's a short, campy, adult sci-fi romp from the early 2000s that knows exactly what it is.