Now that is some sweet, beautiful and tender lovemaking; Iku is beautiful, and I really like that sex position (the Rainbow Bridge, according to the artist).
Sivay/CKLN really does some of the best vanilla Touhou heterosexual porn.
I edited two things in that lovely picture:
-added the "happy_sex" tag. You can't see the guy's face, but Iku has that look that clearly says she doesn't hate it -added the picture to the "making love" pool because of the same above reasons.