[billyhoffman]

You don't want to fire him/her, and the CEO won't fired him/her, for several reasons. Most important of which is, as a co-founder, they have equity in the company, not stock options. Yes, this equity will vest over time but firing with/without cause can change/accelerate things. At the end of the day, you don't want someone who owns a chunk of your company to be pissed at you. This can have ramifications while fund raising.

You need to meet with the CEO, clearly lay out why the co-founders current role is not a good use of time/money/energy, and work to find a new role.