I spent like over 12 hours somehow even though I did not mess around which you really can't do anyways

Navigating through villa area is confusing and than the stealth parts etc. not to mention backtracking segments

I can't see how a speed run would work but maybe I could do it in 10 hours minimum

You're quicker than me - I've never been able to complete it in less than 14 or 15 hours.