It is an adjective and means "it's such a hassle". It is used when you don’t feel like doing something or you feel that someone is hard to handle.
I can’t be bothered to do my homework. I don’t care if I get an F on the exam.
宿題するのが面倒くさい。試験でFをとってもいいや。
宿題するのが面倒くさい。試験でFをとってもいいや。
I don't feel like going to the gym today.
今日はジムに行くのが面倒くさいな。
今日はジムに行くのが面倒くさいな。
Leo is complaining about moving.
- Leo : I’ve always wanted to live in Tokyo, but moving is such a hassle. I’m busy with work on weekdays but I need to pack by Saturday.
ずっと東京に住みたかったけど、引っ越しは面倒くさい。週末は仕事で忙しいのに、土曜までに荷造りしなきゃ。 - Ken : Oh, that’s a shame.
あー、大変だね。 - Leo : After moving, I have to go to the city office and go through the process to change my address.
引っ越ししたら、市役所に行って、住所変更の手続きをしなきゃ。 - Ken : Can’t you carry it out online, can you?
ネットでできないの？ - Leo : No. First, I have to fill out all of the paperwork, and then wait in a line for 30 minutes to register.
できないんだ。先ず、書類を記入して、申請するのに(列に)並んで30分も待たなきゃ。 - Ken : It seems that the whole process takes an hour. It’s such a hassle!
全部で1時間くらい掛かっちゃう。面倒くさっ！
Ken is complaining about his girlfriend.
- Ken : She is such a pain.
彼女、超面倒くさい。 - Leo : Why? What happened?
どうして？何があったの？ - Ken : When we went shopping, she asked me which dress was good on her. For me, they looked almost the same, but it seemed like she was going to get grumpy if I didn’t answer. I told her my preference, but she got mad at me because she didn’t like my opinion.
買い物に行った時、どっちの服が似合うか聞かれたんだ。俺から見れば、どっちもほとんど同じに見えたんだけど、答えなかったら不機嫌になりそうだったんだ。それで、俺の好みを言ったら、俺の意見が気に食わなくてキレた(or怒った)。 - Leo : Oh, I’ve been there. Girls are such a pain in the ass.
あっ、俺もそういう経験あるよ。女って、本当に面倒くさいよな。