Sorry,Flag Time 21 is not avaiable yet. We will update Flag Time as soon as it is released.
If you want to read new chapter of Flag Time at the first time,you can subscribe it. We’ll send your the email as soon as Flag Time 21 updates.

Have more fun on facebook:

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Or enjoy fantasy shoujo moments on tumblr:

https://onlyshoujo.tumblr.com/

You can read some other great manga to kill time