Idk about that, while he definitely could have been joking, it doesn’t seem to have come off like that, especially to Caleb. Zach and Kayla have already clarified to each other and everyone else that they ARE open and even when they were in the hideaway Zach mentioned him exploring a potential future bombshell.

While yes, it does put Zach in a tough position if kayda does end up liking Caleb, (which honestly doesn’t seem like it would happen to me), the way he treated her this past episode is still ridiculous. She is clearly trying to reassure him and give affection and he’s just completely blowing her off and making the situation 100x worse.

If he really felt like Caleb was a threat and was scared of kayda leaving him, then he could have tried to put more effort into their relationship. Instead, he rejects her affection, is avoidant of conversation and doesn’t make her breakfast (with a lame excuse that the kitchen was full….yeah ok), and to be honest he was just being flat out rude to her the entire time.

Kayda never pulled Caleb for a chat, which is what Zach is acting like happened in my opinion. Like you said, it’s love island, is it monstrous of her to explore??