I don't quite remember but i have read past comment. They said, season 1 was shounen ai meanwhile season 2 is yaoi. From another comment from the novel, before the scene in season 2 they already have their first sex.
I think it's mostly a censorship thing. It's heavily, *heavily* implied that they are having sex quite frequently, it's just the scenes are cut out for some reason.
And if you look at the end of the chapter where Eyra has the kinky dragon sex dream there's clearly more to the scene that was just cut out for the English version. It's just really confusing and slightly irritating.
Also, shounen-ai doesn't necessarily mean no sex scenes. There are plenty of shounen-ai that have very graphic sex scenes in them. It just means it's a lil more story driven/romance oriented than standard bl, and even then that definition isn't entirely correct, either. It's just arbitrary definitions western fans came up with as bl became more popular over here in the early 2000's without knowing what the true definitions were.
But I am a lil confused as to why it took them till s2 to actually draw out the sex scenes instead of just cutting to the next day.
It's either that or the English version cut it out for some reason seeing as at the end of the chapter where Eyra has that dream about fucking dragon Yanu there's a cut from the OG translation that shows a lot more of that dream.
It just feels weird 'cause usually the first sex scene is supposed to have some sort of weight to it ((whether positively or negatively)) but after going through an entire season of them fucking around and never seeing it, finally getting one in s2 made it fall flat for me. I was just like "oh ok, so we will eventually get to see them bang" and that was it.