[there's a benefit, at least, to someone like Sinsa being his partner here. compared to most, he's not the type to leave Luke with the lingering feeling of discomfort, the need for some sort of reciprocity.]

I like to think it's fairly simple.

[he... shouldn't be surprised by that question. it's still Sinsa, after all. but
his fingers poke at the hole and that makes Luke jolt a little, a shiver running down his spine.]

... No. It's for penetration. The ovipositor is elsewhere, you needn't worry about it.

[penetration and fertilisation, but that fact is unrelated to the moment. Sinsa isn't the type of Aurorian who would have to worry about it. as to the membranes? well, they're remarkably stretchy. it might take a little work to stretch him enough, but Sinsa's girth would fit. barely.

his ass is a similarly viable choice—and might fit the taller man better—but it'll also require some kind of lube... it's really up to Sinsa now.]