Pinkie Pie throws Twilight a party before her birthday, inviting many of Twilight's friends to attend. As the spiked punch get passed around, the antics of the group become looser. The morning after the party however, holds a shocking surprise for the assistant of Twilight Sparkle.
This story is based of the pic by Lisboa, found here on deviant art http://bylisboa.deviantart.com/#/art/A-Twispike-4koma-attempt-403764196?hf=1