Thank you! I'm so happy to hear that :)
About the narrative, you are totally right. Initially the game was planned to have 2 cutscenes, one at the beginning and another one at the ending.
I had half of the first cutscene done when I started thinking that there was no way I could finish both on time. It was then I had to discard them and add the black screen with plain text. It was that or nothing :/
About the storyline, I'll tell you.
**SPOILER WARNING**
During the game, you discover that the owner of the mansion (the victim), was studying different toxins, as well as his plans to use them on a massive attack. When the detective arrives to the time machine (the origin of the loops) he uses it to come back to the exact moment of the murder, to reveal the identity of the murderer. He waited for the murderer to appear but no one came. He wanted to leave but now that he knew of the evil plans of the owner of the mansion, he had to kill him, revealing that the detective was the murderer all along.
I'm sorry if it wasn't explained as good as intended.
Anyways, thank you for your comment! <3
Pd: sorry if I had any spelling mistake, English is not my native language xD