殘渣餘孽

evil elements who have escaped eradication

to destroy / to spoil / to ruin / to injure / cruel / oppressive / savage / brutal / incomplete / disabled / to remain / to survive / remnant / surplus

remainder / filtered out residue / sediment / waste product / debris / detritus / rubbish

slag (in mining or smelting) / dregs

extra / surplus / remaining / remainder after division / (following numerical value) or more / in excess of (some number) / residue (math.) / after / I / me

surname Yu

variant of 餘|余[yu2], remainder

remaining evil element / surviving members (of evil former regime) / dregs (of colonial administration)

remaining evil element; surviving members (of evil former regime); dregs (of a colonial administration)

variant of 孽[nie4]

son born of a concubine / disaster / sin / evil