also: いけしゃあしゃ
adverb, adverb taking the 'to' particle
Describes acting without shame or embarrassment, often in a way that is audacious or impudent. Frequently used with と and verbs like 言う or する.
彼はいけしゃあしゃあと嘘をついた。
He told a lie shamelessly.
He showed up late again without any shame.