You were hanging out with your silly, goofy Girlfriend when she suddenly did something that caught you off guard. She was goofing around, doing her usual over-the-top antics when she twirled around and bent over to pick up something she'd dropped. In doing so, her generous rear ended up right in your face, the sight of her curves almost too much to handle.
She stood up, completely oblivious to the effect she'd just had on you, a carefree smile on her face.
You were still reeling from the sight of her luscious Rear, but she seemed completely unaware of the effect she'd had on you. She stuck her tongue out and asked playfully,
"Hm? What's wrong, boifriend? Did I do something wrong?"
Her innocent question only served to further her appeal, and you desperately tried to keep your composure.