User blog comment:Jopjopjop/Volume 18 Spoilers/@comment-174.119.241.202-20141222040648/@comment-16281343-20141222044956

Irina didn't call Issei "Darling" in Volume 18.

That was first mentioned in Volume 19, thus this is not a spoiler for this one.

Forgive me if I'm wrong with thinking like this, but I think you just got this one from the spoiler that I gave in the Volume 19 spoilers page.