Well. If I remember correctly, yumiko is a fusion of the three classic nekos. Which means that technically, misaki, yuki, and aiko all got fucked at the same time.
I don't think it counts. It was Misaki reviewing a script and not an actual event.
I knew it was weird they were not noticing Haru's ears and the stolen necklace. And Yumiko isn't supposed to be like a Super Saiyan god like being? Then I realized it was part of the review and not a real event.
In real world Yumiko overwhelms Haru easily. She can only fuck them fused if they allow it. And the 3 nekos tend to be the doms when treating the lewd virus and when just having fun, not the other way around. Does Misaki getting horny would still cause the fusion to fail?
But if Haru actually fucks them fused you could view the fusion as a whole different character. And of course is wouldn't be actually Misaki. Anyways Misaki is not getting fucked any soon, pretty sure Nyakumi is having fun delaying it and teasing about it now that everyone is asking for it.