Regarding the title, the translation’s misleading. It’s translated as “Who do you want first?” which makes it sound like choosing between two girls in a threesome. (“First Anastasia, Minami second.”) However, the Japanese word 初めて refers to a ‘first time’ instead of a first-second-third ordering. Basically, the subtext is he’s losing his virginity. The translated title isn’t exactly wrong, since it can still be read tin that way. However, it’d be better to emphasize the virginity aspect. Maybe something like “Who do you want to be your first?” or “Who would you like as your first?”
Anyway, I‘m emphasizing this because it contextualizes everything else. With plot-driven books, it’s usually safe to disregard the title and let the narrative set the scene. A solid translation’s still preferable, but it’s not critical. However, for books like this, the title sets the scene. Losing the title means losing critical context. So what happened her?
This whole book’s a virginity-loss fetish book. With Anastasia, if you disregard the title, the first explicit reference is with ‘So this is how a girl’s insides feel’. However, we’re supposed to know he’s a virgin well before he enters Anastasia. When she says, “I’m so happy you picked Anya”, we’re supposed to know she means for his first, not ‘picked Anya for today.’ (She’s not forward enough to directly tease Producer about it.) With Minami, it’s why she’s teasing him about being a virgin in her solo part, but also the 3P part. We’re supposed to know that it’s not a follow-up to the previous scene, but a completely different first time. Basically, a lot of ambiguous, unclear stuff makes a lot more sense with a clearer title.