1. Wrapped Up, Olly Murs
"You got the lock, I got the key,"
Lock: vagina
Key: penis
2. We Don't Have To Get Our Clothes Off, Jermaine Stewart
No explanation needed.
3. All My Life, The Foo Fighters
The line "I love it but I hate the taste" is an oral sex reference. It has been confirmed at http://listverse.com/2013/10/25/10-famous-songs-that-are-secretly-dirty/