"Someone is coming down from the Moon?"
At Eientei, Kars was surprised by the news. "There are people on the Moon?"
"Yes. In fact, we originally came from the Moon ourselves," Eirin explained. "Two of my disciples are coming down. We've stayed in touch through letters, but they want to see me in person. It seems humans from the outside world have started arriving on the Moon, and it's causing them a lot of trouble."
Eirin didn't really want to get involved in lunar politics anymore. She had a good life here, and she even had a child. She had no desire to return.
"Since they're coming all this way, I want them to see the life I'm living now. I want them to meet you and get their 'blessing,' so to speak."
Kars had no problem with that.
Meanwhile, Watatsuki no Toyohime and Watatsuki no Yorihime arrived in Gensokyo. Their feelings were complicated. Their beloved master had apparently settled down on Earth and even had a child.
As Lunarians, they had been raised to view Earthly beings as "impure," but they didn't quite share the extreme views of their peers. Still, the idea of their master getting married and having a child on Earth was hard to swallow—especially since they were only finding out about it now.
"I don't know what kind of man he is, but if Master chose him, he must have some redeeming qualities," Yorihime muttered, though she was still skeptical.
"Let's not overthink it. It was Master's choice. We shouldn't say anything to upset her," Toyohime advised. She was more accepting, but she understood her sister's protectiveness over their idolized teacher.
"Just act natural when we meet them."
"I know."
When they arrived at Eientei, they were met by Reisen. Yorihime gave the rabbit a sharp look—she still found it hard to believe a deserter had become their master's disciple.
Reisen led them inside, where they found Eirin Yagokoro cuddling with Kars.
"Is that Master's child?"
That was their first thought. They knew about a child, but they didn't know the gender or age. Seeing how intimately they were huddled together, "mother and son" was the only relationship that made sense to them.
"Master!"
"Ah, you're here."
Eirin looked up, ready to introduce them, but the sisters spoke first.
"Is this the child you mentioned, Master? He's very cute."
"Eh? Child?" Eirin blinked, and Kars looked at her in surprise. Had she not explained his identity in her letters?
"But where is the lover you spoke of, Master? Is he not here?" Toyohime asked, looking around for the man who had captured their master's heart.
"Oh... he... he is my child," Eirin replied quickly, her mind racing. "As for my husband, he's away on business at the moment."
Kars was baffled. Why the sudden change in status? He wanted to speak up, but Eirin gave him a look that clearly said "play along."
"Kars, these are my disciples. Call them Big Sister Toyohime and Big Sister Yorihime."
"H-hello... Mother," Kars said, stumbling over the word. Eirin beamed at him, clearly enjoying the roleplay.
Toyohime and Yorihime were relieved not to have to face the mysterious "husband" yet. They turned their attention to Kars, who they now viewed with great affection.
Kars, taking full advantage of his "son" status, began to cuddle with them and rub his face against their breasts. The sisters merely blushed and gave him gentle scoldings, their hearts softening toward their master's "sweet little boy."
Eirin watched with a mischievous smile, and Kars realized he was going to have a lot of fun with this new role.