I had a look on the comic issues when Sabretooth partnered with the Constrictor.
It seems like Frank was cool with his homicidal serial killer “partner”. Look at this smile and his leisurely posture.
And he did help Sabretooth to satisfy his morbid urge of murder, though he concerned that Sabey was likely to get caught.
Attention: Sabretooth even made a promise to Frank as soon as he was demanded. Usually he would just shot back “so what, not your goddamn business” or some craps like this. He treated Frank soft and that’s not his style. At least not his common attitude facing a merely partner. He only showed the similar kind of tenderness to Holo, Monet, and Bonnie Hale. ←They were all his beloved
Sabretooth was injured, the first thing he did after he re-kept his legs was calling Frank for help. And yeah, Frank saved Sabretooth under the crackdown of 4 heroes when he had the chance to just flee away. He thought he can’t leave his “partner” to ‘em.
Then Sabretooth apologised! He hardly ever apologises as I remember but he said sorry to Frank just because he ruined their job. Frank was alright with that.
They definitely would have comforting s*x after this.
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