Can you explain what heapens exactly? Why you are send 10eth to someone whom you do not know? I guess he promised big profit to you.
You may be right, it could be investments. I think, one more thing is because of donation for a project or token.
To the victim, please be specific on what exactly happened. Why it turned out on scamming you and the other.
If it is about newly created tokens and projects, they have been scammed by a poser, who made them beleive that he is part of the team or developer.