I'm wondering if Issei's breast translation ability should be called Booblingual instead of Bilingual.
First of all, the word Bilingual means speaking two languages, but doesn't specify any one language. It's not a sufficient name for the power.
Second, I think the name of the power is supposed to be a pun for "oppai (オッパイ)" and "bilingual". So in Japanese, instead of "bilingual (バイリンガル)", it might really be spelled "ppai-lingual (パイリンガル)", which directly translates to "Booblingual".
But the only way to confirm this for sure is to find the word from the original light novel, and see how it's spelled in Katakana. Can anybody confirm this?