Different anon but Sonar x a plant hybrid (or anyone x a plant hybrid reader tbh)
Reader used to be a normie but then got mutated with plant dna, and that did something funky with their body, changing part of their anatomy like their genitalia. They have something similar to human male and female reproductive parts, somewhat comparable to some intersex individuals (I know being intersex isn't the same for everyone) but then there's parts that aren't human at all, like pistils and stamens, or what looks like a labia is actually more akin to flower petals, etc. It's different from how the reader's original body was and they haven't been intimate with someone in a while because of it. They're unfamiliar with their own body and don't know how other people will react to it.
Oh man the fact that you haven't tried to experiment with your new body, he feels obligated to help you discover your new genitalia.
Sonar also has some nectar feeding bat DNA in him, so he is immediately drawn to you the second you confide in him about your issues. He was also literally drawn to you because he could smell a sweet scent that now he knows comes from your crotch.
Sonar smells your arousal on you, which is essentially your flowery petals opening up, but you don't exactly know that yet.
He keeps poking around with his hands, asking how it feels for you. He even keeps notes, trying to draw parallels between what parts are like human genitals and what parts are more like plant reproductive parts.
He likes calling what is obviously your labia, your petals and what is clearly your penis, your stigma.
Once you feel a bit better about your own parts, he asks if he can indulge himself. After he gets the ok from you, he dives nose first into your scrotch, sniffing and licking around, just trying to get as close as possible and smother himself into you.
Now hear me out on this part.
Little budding flower nipples. What we consider regular nipples hardening is your flower buds opening up. So just picture Sonar teasing your little buds with his fingers and tongue, just cooing and lapping at them with his tongue when they open up for him.
ps if anyone could tell me what to tag for a reader with both genitals, I would appreciate it.