1.Click Login located in the upper right hand corner of shop.crunchyroll.com
2. You will automatically be directed to the log in page of crunchyroll.com
3. After entering your credentials, click "Log In" and you will be re-directed back to the Crunchyroll store.
4. That's it! You are now logged in!
Note that if you are logged in Crunchyroll.com, the Crunchyroll store login process is only 1-click. If you are logged out of Crunchyroll.com, you will need to repeat Steps 1-3 to log in back to the store.