Lucas had been on that chair for more than an hour or two selling cupcakes and cookies to customers. He knew his learners were preparing something but he was just down, he didn't feel like doing anything as his marital problem was heavily placed on his chest.
He had forgotten how to cope with his wife, understand her and be patient, he had just...ah, it was hard and he hated the fact that she knew who he was.
So, he decided to go to his learners to at least let his mind off his family problems.
He was glad to have them with him as their childishness was fun and crazy. Everybody needs something crazy at some point and he had eight of them even though he scolds them sometimes and he just didn't know why he always wanted to scold Kath.
He just mentions Genevieve because everyone would notice his obsession with the white small girl. And she was beautiful and hot!