Ryuki also wanted to make Yuta and Asuka's mother his lover. For that, he asked his gift for a way, and his gift told him to wait until next March.
Ryuki remembered that he was not allowed to visit Machiko's office in March, June, September, and December.
He didn't know why Machiko forbade him from visiting her office, but now, only by going to her office in March could he start his journey to get into her pants. Of course, there were other ways, but those ways required him to lie, manipulate, and do other unethical things.
Ryuki doesn't want to go down this unethical path if possible, of course if there was no way but to do this unethical thing, then he might do it or not. He wasn't sure about it himself as well.
Anyway, he knew that he needed to wait for March before doing anything to Machiko, so he set his eyes on Rena.