In all honestly, Xander was too shocked to reply, much less react. Heck, he swore he even stopped breathing for a second. Spike was kissing him! Kissing him.

When Spike pulled away, Xander could only gap and lick his lips in awe. "I...umm...wow." When he'd gotten up on stage that night, this had definitely not even been in the scop of what he thought might happen.