(2channel slang, dated) Please die.

(colloquial) Synonym of 行って来ます (itte kimasu, “see you later”)

to go and come back

Alternative spelling of やってくる

past of 歌ってみる (utatte miru, “to try to sing”): tried to sing

utattemita, a class of music where 歌(うた)い手(て) (utaite, “amateur singers”) cover songs

(Internet slang) Alternative form of いってら

to be coming, to be arriving

to come back

or rather / (informal) Used to change the topic and introduce one's realization that something is strange.