Interesting theory, Hector seem indeed a logic choice too but it's not the style of Hector to jump on girl cleavage. Beside the demon seem like Winnie and Hector didn't liked Winnie in the begiining in the old comic. It could be a part of the change made by the author to ameliorate the story.
We will see that soon enough since Winnie squealed so strong that she broke the cristal. It's a nice change, now instead that break suddently without apparent reason, we have a fatal sonic attack. Spring is now doomed to age and die.

Let's just hope that the cat didn't escape of fear to be killed.
Ce fut une bataille facilement gagnée si vous voulez mon avis.
S.P.P.