Alrighty then.
The riddle: I am a builder, yet I'm unlike you. I am... Beaver
I think if I add more clues i would be simple... A, B and R were found out by LioNeeZ.
Hinode gave the correct answer.
Hi Esan
Could you check this one? 少女性活記録チグサちゃん
Somehow there is another game in the archive. And maybe you'd be able to share a newer version
Thank you for your work!