Clash of Clans – What Happens to an Inactive Account?

from https://productforums.google.com/forum/#!topic/webmasters/XTmiHxe-VsI

Log into the google+ account, select the "Home" drop down in the upper left hand corner. Select "settings", Scroll down to about half way down and select "Manage apps and activities", Select the edit (pencil) tool for clash of clans and select "disconnect". Make sure you check the box that asks about erasing all activities for this App. It takes about an hour for Google to erase all data for the app, but after that you can then re-connect with the account you want to use.

and another one http://cocland.com/tutorials/removing-clash-of-clans-from-google-account

This was not an easy thing to track down via Google or even clicking through my Google+ account menus. Hopefully this may help others.

Yes this is possible. What your friend is going to need are at least two Google accounts linked to his phone.

First, from within Clash of Clans, go into settings and connect the current village to a Google+ account. This will allow him to restore his village from any device that he signs into his Google account from.

Then in Android,go to settings -> Apps -> Clash of Clans, and 'Clear Data'. This will wipe the village off the device, but it will still be linked to the Google+ account.

Now open Clash of Clans again and get past the intro tutorial. On your iOS device, open Clash of Clans, go to Settings -> Link a Device -> This is the old device. On the Android phone, open Clash of Clans, go to settings -> Link a Device -> This is the new device. Follow the steps to link the Android phone to your village. Now connect the new village to a second Google+ account (Must be different than the first one!)

Now any time he wants to switch between the two, he just simply needs to Clear Data as explained above. After loading Clash of Clans, he will be able to sign into a Google+ account (there's now an option to do so without doing the tutorial), and restore its respective village.

I just tried this entire procedure and verified it works.

For future reference, it appears that Android phones will soon be getting user profiles. So that like Android tablets, different user profiles store different sets of user data. When this feature comes out, it would be possible to setup each village on a different user profile and just simply switch between the profiles, no clearing user data needed. Though I would always recommend linking each village to a Google+ account for safety.