Can you imagine what Bescumber means? I tried really hard but, couldn't.
It means in its exact definition (I take no credit for it): bescumber is just one of many words in the English language that basically mean “to spray with poo”. These are: BEDUNG, BERAY, IMMERD, SHARNY, and the good ol’ SHITTEN. In special cases, you can use BEMUTE (specifically means to drop poo on someone from great height), SHARD-BORN (born in dung), and FIMICOLOUS (living and growing on crap)
WTF that dude just bescumbered you!