Suspect a song lyric implying a word 「君といつぃまでもずっと一緒に」
I'm trying to figure out what seems to be an implicit word in the song lyric 「君といつぃまでもずっと一緒に」, and that's the very first line in the song, so not a lot to go with in terms of context, though the next line is 「いつまでも私にキスを下さい」implying a する in that line, which is why I suspect the previous line is implying a word and I doubt a sentence would randomly end with 一緒に as 一緒だ would be the grammatically correct one wouldn't it?
I'm suspecting it to either be 「一緒にほしい」(though I'm pretty sure you'd need to use a が rather than a に in that situation) or 「一緒になりたい」but I'm not completely sure and any help or explanation would help would be appreciated.