I think Yashiro want to have sex with him once then tell him that you should leave because...

I think Yashiro want to have sex with him once then tell him that you should leave because you don't belong to this world ......so Doumeki I think he will refuse ......or Doumeki will make a gentle
sex to Yashiro and the surprise that Yashiro will love it and discover something he never felt it before