If he hadn't been here I would have put the container on the floor and poured the water in safely, making sure it only splashed on things that would dry easily, not be damaged. But he was there, and I set the container on an uneven surface of a folder containing his notes for class, next to his digital camera. He watched me as I began to pour. The room was dim and I guess I was feeling reckless. He cautioned me to be careful with the water. I continued to pour, sure that it would be fine. He grabbed the camera just before I splashed an unhealthy amount of liquid. He got upset, I felt indifferent. Anything is fixable, I figure. He accused me of being irresponsible with his things. He's somewhat right. I suppose there are a few reasons why:

1) I can be fairly irresponsible with many "things". I treat them as replaceable. Mostly my things and I guess Dans things are now under the veil of my things, since we share them so often.
2)I must like to rile him up. Not consciously, since I don't like being yelled at, especially if I know I'm mostly wrong and don't have a solid, winning comeback. But we have a pretty calm relationship, and this is something we've talked about before and, aside from not leaving his laptop on the floor(something HE does sometimes, ahem) I haven't tried to make a conscious change.

In conclusion, we fight because he's right. This time.