The phrase isn't common but for someone to say something like. "I just needed to vent" is very common and I hear my wife talking about it alot. She works with people in retail and the workers often come to her to complain about some annoying customer. They might tell the story to her and then say "i just needed to vent"

You just remove the word "out". You can vent your anger and vent your frustration. You will see both of these written more often than spoken. In spoken English you will hear "I just needed to vent" I just needed someone to vent to" and the more colloquial "I need to blow off some steam." Yes, manga is a great resource IF it is one you really like. It also helps if you already know the story. Dr. Krashen, the man behind so much language acquisition research, absolutely endorses manga, comics, fiction, magazines and anything that you really like. For French I managed to find Naruto in manga. For English you will have a ton of choices! J

“To Vent”usually suggests that you want to let off some steam and get something off your chest. So you don’t need to say vent out your anger.