"nobody on the internet knows you are a dog" - make your pet dog/cat/hamster a co-founder/imaginary friend. Create a facebook page/github account/stackoverflow account for them so they exist on a cursory Google search. At a later stage after you have done the money grabbing explain that your co-founder didn't really commit much code and you had to let him/her go. Dishonest? Yes, but women that posed as men to get publishing deals or to join the army were dishonest too. In the current scene there is this 'must have cofounder' rule that doesn't entirely make sense. It is mythical man month to a certain extent - if one person spends two years to develop an MVP and get traction that is somehow worthless whereas if a team of two do it in a year that is somehow perfect.
If you're making up imaginary partners to get someone to give you money when they wouldn't otherwise, you'd be committing fraud. If the investor found out, they could press criminal charges[1] or sue you to get their money back. (They'd be especially likely to do this if they lost money on your company.) Once the case ended up in court, you'd have no way out, since continuing to assert your lie would be perjury (a felony).
