"Gossip Girl's" Blake Lively is dishing to Allure magazine about her man Penn Badgley -- and why she feels like a "tranny"!

After seeing so many celeb relationships crumble, the 21-year-old tells Allure she decided to keep "a vow of silence" about her relationship with Penn Badgley... though she'll admit Penn is a phenomenal pianist!

The 5'10" blonde beauty admits she doesn't always feel 100% feminine when she's dressed up for red carpet events. Lively jokes, "I feel like a tranny a lot of the time. I don't know, I'm... large?" She continues, "They put me in six inch heels, and I tower over every man. I've got this long hair and lots of clothes and makeup on. I just feel really big a lot of the time, and I'm surrounded by a lot of tiny people. I feel like a man sometimes."

For more candid bites from Blake Lively, check out the May issue of Allure magazine!