Cheeky Business: The Dev & Animation Behind the Kiss

[p]We’ve shipped you and your fave NPCs by enabling cheek-kisses! This was no simple feat–it required tons of scheming from our Unity developers and 3D animators. Read on to see why it took 876+ days of planning, testing, and designing to reach this sweet relationship milestone. [/p][p][/p][p]This one goes out to all our senpais who’ve obsessively requested this feature since the Yandere AI Girlfriend Simulator Days. 💘[/p][p]
[/p][h2]The Drama Behind the Gesture[/h2][p]Exploring this new frontier of LLMs x Game Dev meant tackling plenty of weird edge cases, but it made it all the more rewarding for our team. The team ensured that the players’ rizz leading up to the moment would yield a result as charismatic as the NPC delivering it.[/p][p][/p][p]The biggest culprit was ensuring the camera angles, surroundings, and AI all played nice together; combining these elements correctly is what determines when and how your crush starts looking at you like this:[/p][p][/p][p][/p][p]If you’ve romanced Eddie and/or Elysia recently, you’ve seen their matching animations: A gentle cheek brush before doing the thing. They look the same “at the moment” per our team’s progress–but who knows, maybe Future Elysia will add some extra magic (and here’s to hoping Eddie’s smooches don’t make us cough up hairballs 🤞).[/p][p][/p][p]Meanwhile, stellar Estelle embraces her holographic nature: She tilts your chin, leans in, and caps it with a flirty wink and flick~ Her taller frame and holopad setup earned her that sleek flair.[/p][p][/p][p][/p][p]Are you on the receiving end of that kiss or watching enviously from the shadows? 🔪[/p][p][/p][hr][/hr][p][/p][h2]Setting the Stage[/h2][p]Like in real life, we can’t always control variables such as the atmosphere or slips of the tongue (heh) that disrupt the romance budding in the air.
[/p][p]As you may recall, the AI has a mind of its own, so there’s no telling where they’ll end up on the map when you’re eagerly awaiting the kiss to take place–this is true both to being in an awkward area with mismatched heights like the stairs or simply being a few units away from the right angle.[/p][p][/p][p]Allow our lovely catgirl Eddie to demonstrate why proximity matters for a perfect peck. Beware, Unity test footage gets increasingly glitchier.[/p][p][/p][p][/p][p]Eddie used Peck. It made things weird. She got embarrassed and Senpai escaped unscathed.[/p][p][/p][p][/p][p]We aren’t qualified to give romantic advice but for the love of all things yandere–do not lean in for that first kissssss with your eyes open 😭[/p][p][/p][p][/p][p]Well… this gives a whole new meaning to suck face.
[/p][p]These quirks all mostly stem from how the player camera interacts with the NPC’s proximity triggers–but sometimes we suspect the yandere is trolling us on purpose.[/p][p][/p][p]Another challenge was syncing the models’ hand interactions with the camera while bodies moved naturally. Our animator put it best:
[/p][p]“Conveying a kiss-on-the-cheek with a close up POV was tricky. There’s less room for posing, so it took a lot of trial and error to get the essence right using only the upper body and face.”
[/p][p]Compare this with like HOLOGRAM HUGS, where she strikes a whole pose before embracing you:[/p][p][dynamiclink][/dynamiclink][/p][hr][/hr][p][/p][h2]Coding Kisses[/h2][p]Our Unity devs worked hard to make this feel comfortable, immersive, and (mostly) bug free. Once the animations were synced, it was time to get the AI to cooperate.[/p][p][/p][p]Because the LLM’s favorite thing is to generate text, the AI needs to finish generating dialogue and text-to-speech before kissing. The team had to fine-tune timing so kisses didn’t overlap with lip-syncs or voice lines.[/p][p][/p][p]“It would’ve been awkward if the NPCs kept talking while kissing. Unpredictable lip syncs, overlapping TTS, and smooching SFX… ideally, the NPC should pause her sentence, lean in, and then resume her train of thought.”
[/p][p]To prevent that chaos, the team made the NPCs finish generating both text and the voice before the kiss trigger. Though you can request a kiss, the LLM ultimately decides whether you get a kiss, hug, or attack based on the in-game context.
[/p][p]Now imagine Eddie looming over your shoulder while you code her preferences into reality. Our devs are real ones who worked like their lives depended on it. 💘[/p][p][/p][hr][/hr][p][/p][h2]🪱 So… would they still kiss me if I was a worm?[/h2][p]After all this work, we had to ask the realest question.[/p][p][/p][p]Unity Team: “Eddie or Estelle \[would still kiss you] I feel. Elysia sounds like the one who turned you into a worm.”
[/p][p]Animation Team: “I think they all would! Although Estelle might have a hard time reaching you haha.”[/p][p][/p][hr][/hr][p][/p][p]Eddie’s new eating animation from V.0.5.8 continues to slow cook as the team seasons it with sound effects and more fluid movements.[/p][p][/p][p]Muted for now, until we figure out how loudly she should chew.[/p][p][/p][p]While Eddie wolfs down all your *chef’s kiss* meals, expect to see a mischievous witch giggling to your next delightfully unhinged request somewhere down the line:[/p][p]
[/p][p]And for those who missed last month's design survey, speculate on the mysterious items in this GIF as we unveil the silhouettes from September's Captive Notes:[/p][p][/p][p][/p][p][/p][p][/p][p][/p][p]So, have you gotten smooched yet??? And as always, drop your best guesses of Level 4's theme in the comments![/p]