One theme could be the pride of the narrator. He is so concerned about out-smarting his friends that he, in effect, out-smarts himself, by moving his bed to the middle of the floor and making his room dark. When the valet trips over him and spills his breakfast, he is not being “pranked” – the valet simply could not see him and did not expect to find a mattress in the middle of the room. So in a sense the “prank” is the narrator’s own suspicious nature!
Another possible theme could be appearance vs. reality: the narrator is paying close attention to the behavior of his friends, and his interpretation of their good spirits is that they must be up to something. The reality of the situation is not really available to us as readers; we can assume, however, by the events of the story that the narrator was wrong about his friends.
A third possible theme is paranoia. If we think about the narrator as someone who is paranoid, then his actions and suspicions take on the character of mental illness: everyone is out to get him; even though he will go to any length to avoid being pranked, jokers are the only sort of people he cares to know; his suspicions cause him to behave in an irrational manner (by moving the bed and assaulting the valet). Even the final line of the story (“How they all laughed that day!”) suggests that despite all his efforts he has been “gotten” in the end.
Finally, another theme could be victimization. The tone of the story is very light-hearted, but there is an edge to it – a sense that perhaps not everything is as happy as the narrator would have us believe. We don’t have much information about the relationship of the narrator to these “friends,” but there does seem to be an abusive element to it. Another aspect to this theme would be the idea that the narrator is self-victimizing; why else would he prefer to associate only with practical jokers, unless he somehow enjoyed or desired to be the object of such jokes? In that case, the end of the story, and his reflection on his friend’s laughter, could be an expression of gratification: their laughter affirms his value as a suitable “target” for their pranks.
The theme of "The Uncomfortable Bed" by Guy de Maupassant is you get as good as you give. The gentleman is visiting friends who are practical jokers, and he admits to being one himself. This makes him very suspicious when he enters the bedroom in the chateau. He hears laughing outside of his door and thinks that his friends are waiting for him to be the subject of one of their jokes. After lighting all of the candles and securing the windows, he stays awake. Soon, he decides to retire to his bed but not before remaking the bed on the floor. In the morning, he is awakened rudely by the butler who trips over the visitor while delivering the morning tea. Hot tea spills all over him, which he believes to be an awful liquid. In the end, the joke was on him.