Drink Release Device Concept

People claim nothing is new under the sun, so this concept might have already been shared as a method of release. I envision a tall container filled with water, inside which sits a float attached to a rod extending from its top. The rod slides vertically through several guide rings and rests against a stop at the upper end. Once the vessel is full, the buoyant force pushes the float hard enough against the stop to trap a key between them. As you drink through the straw, the water level drops until the float descends, freeing the key. It’s important to make sure you can retrieve the key once it falls into place. The delay duration depends on how much liquid needs consuming, or you could use a small amount of something gross (like urine?) as an emergency release trigger.