The first thing Kurt heard was white noise as Blaine pressed his lips to Kurt's as soon as the ball dropped on the TV.
The second thing he heard was a shrill scream that slowly turned into an excited squeal.
When Blaine pulled back five seconds later, Kurt realized his arms had twined around Blaine's shoulders and was holding him in place. He then realized that the scream/squeal had come from Blaine's older sister Rachel Berry.
Of course, he should have known, no one else has that kind of shrill scream except her.
She looked both horrified and delighted, which overall just made her look happy and sick at the same time.
"I don't know whether to kiss you or hit you!" Rachel said, running towards them.
Blaine rolled his eyes and backed Kurt against the wall, sealing their lips together again as Rachel began talking their ears off.
Kurt lifted a hand off Blaine's shoulder and pushed Rachel away before tangling his hands in Blaine's loose curls.
Rachel squealed again before running off, yelling something about 'New Year' and 'camera'.