A jealous and envious person will see things in a much different light than the others
Kence just genuinely wants to get back at Calter a bit since the hateful was giving the people around the impression that Kence is the submissive one
Of course, in the past, Calter is mostly the top and Kence is mostly the bottom but we should ignore that fact for the latter's pride
To Eriel however, Kence was deliberately acting intimate to the man that she deeply loves and that is unacceptable
That is an action enough to incur all of Eriel's wrath that she cannot unleash even if she doesn't want to
"The both of you look good together. I'm glad things worked out since one of you gave up in the past" Eriel said as if she was genuinely glad that the two were together again
That causes Kence's mood to darken. Him giving up on Calter that literally risked his life to save him was the darkest past that he had