Ok, what he said last chapter made sense to me now.
So, as many speculated, he tries to help Mitsuki solve her problem with her dad (probably before he himself leave her)
Now, the conversation from last chapter and this chapter are combined into this:
- Mitsuki said she wanted to cut her dad off and don't want to go talk to him.
- Takase asked, if he hypothetically do the same thing, will Mitsuki also cut him off?
- To which, Mitsuki answred, if he did that without a reason, then she supposed she'll do that.
- And Takase then pointed out, then, let's find this reason out first and decides what to do later.
Probably to lead to when Takase will leave her himself.
We could also say Takase sees himself going to be the next person leaving her, the same way her dad did, so he tried to untangled this beforehand; otherwise Mitsuki might not listen to him when the time come?