The outside of Milk Shake actually looks like a giant milkshake. It has the colors pink, white, and a little blue. The name "Milk Shake" is written in purple color. It appears to have an open door and also a single window just beside it. It also has lights around the top and just over the door. It looks slightly like the Chum Bucket.
The inside of Milk Shake is in very good condition. It was run by Younger Frostymug (though he might just be an employee there). It has pink walls and purple and white tile floor to match the exterior. It had a milkshake machine which is located behind Frostymug. It had chrome-like chairs and tables and even had posters of milkshakes.
Milk Shake, like above, only appears in Captain Frostymug's flashback when he starts to cringe when trying to blend a milkshake. The place appeared very popular to kids and teens and they loved Frostymug's milkshakes. However, things turned sour when Frostymug was blending a milkshake and some of the ice cream landed on an electrical wire. This caused the milkshake machine to malfunction and it sprayed ice cream in all of the kids' faces and they ran around screaming (probability due to the ice cream stinging in their eyes). Milk Shake isn't seen again after the flashback sequences ends.
It is unknown if Milk Shake was closed down after the milkshake incident.
Milk Shake seemed as if it was around in the 80's or 70's due to the fact that it complied with the 70's (Dance/party theme).
Milk Shake may be similar to the Tropical Smoothie Cafe Franchise, which makes Smoothies, similar to Milk shakes.
It also may be similar to the Carvel Ice Cream store franchise, because Carvel also serves ice cream and milk shakes, it is likely that Milk shake also serves ice cream.