Awkward Attempt at Sexy Times (AAST) is when your sexual overtures are rejected due to inappropriateness of situation or setting. The key difference between AAST and being creepy is that in this case the object of your affections does not feel threatened or in any way afraid of you. They just think you're pathetic.
You and your new girlfriend stopping by at your ex*'s house unannounced to ask if she'd like to go get a drink with you all. This is an Awkward Attempt at Sexy Times.
*Bad break-up and someone you're not friends with now.