Shinseki No Ko To O Tomari Dakara De Vahana Exclusive ((link)) -

Shinseki no Ko to Otomari dakara de wa nai " (親戚の子とお泊りだからではない) is an adult-oriented visual novel (H-game) typically categorized under the "Innocent Grey" or similar thematic styles, though it is often discussed in niche circles for its specific "exclusive" or "fan-disc" content.

It might relate to "Shinseiki Evangelion" (新世紀エヴァンゲリオン) – but "Shinseki" is missing the long vowel, and "no ko" is strange. Shinseki (relative) vs. Shinseiki (new century). shinseki no ko to o tomari dakara de vahana exclusive