AI Video Consistent Characters: How OiiOii Keeps a Face On-Model

AI video consistent characters: how OiiOii keeps a face on-model

Ask anyone who makes short comic dramas or fan animation what breaks AI video for them, and the answer is the same: the character won't stay the same. The face shifts. The hair accessory disappears. The eyes change color between shots. For a genre where a character's likeness is the whole point, that isn't a rough edge, it's a dealbreaker. Consistent characters are the hardest problem in AI video, and they are the one OiiOii set out to solve.

It was the most persistent pain point that surfaced in interviews with short comic drama producers. Creators want absolute facial fidelity: face structure, hair accessories, eye shape, iris color, all matching the reference character sheet, in every single shot. When OiiOii started, no reliable solution existed on the market.

Why most tools lose the character

Most tools generate each shot independently. That's efficient, but it means the model has no memory of who the character is from one shot to the next. Worse, the scene bleeds into the face. Put a character in a dark dungeon and the lighting and mood start dirtying the facial rendering in ways no one asked for. By the third cut, the person on screen isn't quite the person the creator designed.

The fix: face ID as the anchor

OiiOii's answer was to stop treating the face as one more thing the model guesses at, and start treating it as the authoritative reference. A close-up character face reference is injected independently at storyboard-generation time as the primary anchor in the agent pipeline. The face ID is the source of truth; the scene works around it, not over it.

Getting there took more than a hundred rounds of internal testing. When follow-up research showed scene conditions were still contaminating faces, the team ran a second development cycle: targeted fine-tuning of the face-identity model, a separate facial data set kept independent of the scene, and user control over character portrait swaps. The result is a face that survives the dungeon.

Listening to the hardest users

The clearest signal came from the most demanding creators. One high-caliber game fan-content creator spent an entire week on a single short, combining AI with frame-by-frame retouching. She tried OiiOii and left because some fine-detail editing needs weren't met yet. That's the kind of feedback it would be easy to dismiss as an edge case.

OiiOii did the opposite. Product managers and the operations team sat with her at her workstation for three hours to hear every step of her workflow. In the otome genre she works in, player expectations for character likeness are uncompromising, and her standards were a gift. The features that came out of that session, frame-level storyboard decomposition and reverse-prompt inference, now serve every creator working at that level of precision.

Keeping AI video consistent with characters on-model across every shot isn't a checkbox OiiOii added. It's the problem the team kept re-solving because users wouldn't let them get it wrong. Anyone who has been stopped by drifting characters can try it at oiioii.ai.