Ore to Kawazu-san no Isekai Hourouki - Vol. 4 Ch. 35

[dethduck]

@desaurido
He can't call her by her name if he wanted to. Kawazu screwed up the translation magic when he summoned Tarou there. Whenever someone tells him their name he's not able to hear it. That's why he makes up nicknames for everyone he meets.

 

[desaurido]

@dethduck Sailor soldier is an isekai person and speaks japanese, so he can hear her name just fine. He decides to keep calling her with nicknames because he is a troll. This was mentioned when they first met.