unremorseless
Un`re*morse"less, a. Etym: [Pref. un- not (intensive) + remorseless.] Defn: Utterly remorseless. [Obs. & R.] "Unremorseless death." Cowley.
Un`re*morse"less, a. Etym: [Pref. un- not (intensive) + remorseless.] Defn: Utterly remorseless. [Obs. & R.] "Unremorseless death." Cowley.