거라곤

that …

→ 것
phrase Rare #21,837
that … A shortened form of 것이라고는, used to emphasize a thing or action, often with 생각하다 (“think”) or 뿐 (“only”).
KO: 그가 하는 거라곤 불평뿐이야.
EN: All he does is complain.

내가 널 좋은데 데려갈 거 라곤 생각하지 마라

Don’t think I’m going to take you somewhere nice.

— 400번의 구타 (1959)

주연이 될 거 라곤 생각지 않는다고 썼죠

I wrote that I don’t think they’ll be the lead.

— 오디션 (2000)