When I was a teen, most of my enemas were standing up. Most times, the purpose or goal of the enema was not a full cleanout, but just for fun since the feel of the warm water going in was the best part, so multiple small enemas with the bulb were what I did standing at the bathroom sink. Easy and quick even if I only had a few minutes to do it. And I know my sister was of the same mind, at the time.
I remember one evening when mom and dad were out, I heard water running in the bathroom. I had to pee, so thinking my sister was washing her face, or hair, I just walked in. There she stood at the sink, naked from the waist down, bulb in hand, waiting for the water to warm up. She said, "In or out, but shut the damn door." I walked in and shut the door saying I had to pee. She said, "Then do it", and proceeded to give herself a couple of bulbs while I sat there peeing. When I got off the toilet she held out the bulb toward me and she said, "You might as well do it as long as you are here. I know you do it too." And so I did. We took turns giving ourselves a couple of bulbs, letting it out, and repeated that several times.
Even as an adult, sometimes a couple of squirts, standing at the sink to get the lumps out gives me a good feeling when I don't have time to get out the bag, and all of that prep and cleanup that comes with the bag.