tu cum sis quod ego et fortassis et fortassis nequior, ultro
insectere velut melior verbisque decoris
obvolvas vitium?
Translation:
While you are no better and maybe worse, wantonly
do you strafe me as if you're better, and you cover up with respectable words
your own vice?
quod: I can't parse this.
ego: ditto.
I am guessing that a longer from would be: tu ... sis quod ego sim:
Question mark: this tells me that the sentence is a question, but how did the editor know this?