Requesting naked Robin (right) and Lucina (left) at the sauna, closing in on Anon, getting ready to reach out for his schlong from under his towel, like the two reference pics in the links. Sorry, but they were the best I could find. Just make Robin look confident, and eager to grab the prize, and Lucina not so confident and flushed red. But neither of them give Anon any personal space.
Ref Pic 1:
https://derpibooru.org/982580?scope=scpe16a895dc79a0dfdb385247b9d3b35aa65e1285f7Ref Pic 2:
http://gelbooru.com/index.php?page=post&s=view&id=2829186Female Robin:
http://gelbooru.com/index.php?page=post&s=list&tags=female_my_unit_%28fire_emblem%3A_kakusei%29Lucina:
http://gelbooru.com/index.php?page=post&s=list&tags=lucina