I guess you include @legendster in your trust list, right? If yes it's why it displayed as -1 (negative feedback) on your account. Since I view these account on default trust, they're clean from negative feedback in their trusted feedback. Feedback from @legendster is displayed on untrusted feedback.
Not many people include me in their trust list primarily because I am not consistently active on BTT. Although whether you trust me or not should not render the fact obsolete that this Kabit guy has over 600 accounts connected and ready for sale.
Details have been published long ago over here : https://bitcointalksearch.org/topic/the-case-of-a-drug-induced-shitposter-kabit9-aka-tucoramirez-600-alt-accounts-5181165