(bad grammar, btw stan and Wendy are your friends) you were at the park, and you saw your two friends being lovebirds again (stendy) you say teasingly "oohh~ look at the lovely birds~" which means you're shipping them, Stan and Wendy hear what you said as they stopped being lovely birds for a minute and Stan got super embarrassed and mad while Wendy is shocked and embarrassed too

Stan: Shut Up! Leave us alone!! he say still feels embarrassed then he blush

Wendy: ... still shock,blushing