るりじゃありませんでした
瑠璃蜚蠊じゃありませんでした
ruri jārimasendeshita

Noun
Desu Copula

The polite, past negative form of るりごきぶり

1. Was not a cockroach.; Was not a jewel beetle.

Past/Perfective
Negative
Polite
Terminal Form
Usually Written in Kana