So many questions about this show - the writers will never answer and Episode 7 of Season 5 really made this question mute, but I have been asking it anyway - maybe you guys have the answer? I'm saying Tamsin was toast when Bo fed off her in her previous life during Episode 6 of Season 3 while tracking down Kenzie who was being held captive in the "creepy cave by the dump off of Highway 6" by the Kitsune. I'm not 100% sure though because Bo's got "Hybrid Blood" and probably a few other "hybrid" features and it seems that she may be able to "hook into" her food sources on the very first "tasting" - which would mean Episode 3 Season 3 when Vex brings home the parasite and Bo, Tamsin and Dyson revert to teenagers and play spin-the-hair product. Even if she couldn't remember, there might have been a residual chi exchange that made Tam Tam soften towards Bo.