Yep, pretty much. Basically, Katou does not want to engage in anything overtly sexual with anyone he actually cares about. He doesn't have romantic feelings towards Tree, but he does care about him, which files him directly into the "lol nope" category for sexytimes. It keeps something of a barrier up for him. It's also why he tries not to care about too many people— he doesn't want to let people get close and risk getting hurt. Teamdere fucks that up enough as it is without getting sex involved.

Do you think Turquoise, or at least Tsunami, stands a chance of topping Tree out of his new, shiny touch issues?