せぐろかもめじゃありませんでした
背黒鴎じゃありませんでした
seguro kamomejārimasendeshita

Noun
Desu Copula

The polite, past negative form of せぐろかもめ

1. Was not a black-backed gull.; Was not someone with a dark past.

Past/Perfective
Negative
Polite
Terminal Form
Usually Written in Kana