https://www.dlsite.com/girls/work/=/product_id/RJ385201.html
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This one is translated to english!

First love. First time... A happily married couple experience their first time, together.
It seems like they have a lot of "first times" in common to share!

Shinji and Airi first met one-another at university. They fell in love and decided to get married.
On their wedding night, Shinji is keen to "start making a family," but Airi is still a little anxious about what is to come... both mentally, and physically.

44 pages total (1 cover + 43 main pages)

Artwork / Scenario: Koi Tanihatsu
Assistant: TogenoRow

Second part (Japanese): /g/2702854/81ad4c3355/