Games : transfer Clash of Clans account from one G+ to another G+ account

I want to give my account to someone but I want to keep my G+ account. The reason is I hold this G+ account very dear to me and I can't give it.

I've watched some clips about transferring accounts to another device. But I haven't found a video how to transfer Clash of Clans account from one G+ to another G+ account.

I am using android OS.