Konata
Now Definitely 100% Legal!
This was a flash game from around 10-15 years ago. You played as a young girl whose sister was kidnapped by some chef looking guy promising free candy. He also kidnapped you, so your objective was to go throughout his creepy, dilapidated home to find your sister and escape. I also remember the first area was in the basement where there were stairs and the chef guy would check in on you if you made too much noise. picrel is what i remember the title screen looking like