There is much satirical humor in the scene in which Bottom has his head changed into a donkey in Act III because the responding characters become the impetus for actions of the and responses of Bottom. First of all, when his head is changed into that of a donkey/ass, Quince cries out,
O monstrous! O strange! we are hauted. Pray, masters! Fly masters! Help! (III,i, )
Then, when Scout returns and tells Bottom "thou art changed!"(III,i, ), Bottom unknowingly replies,
What do you see? You see an ass-head of your own, do you? (III,i, )
And, still unknowingly, Bottom continues his unwittingly funny allusions to ass:
I see their knavery: this is to make an ass of me, [he has literally been made into an ass!], to fright me, if they could. But, I will not stir from the place, do what they can: I will walk up and down...and I will sing...(III,i,105-106)
As soon as Titania sees Bottom, she falls in love because of the potion administered to her. And, because the sight is Bottom, her love is absurd. When Titania tells Bottom, "I love thee" (III,i,133), Bottom replies with an ironical pun:
Methinks, mistress, you should have little reason [no justification/no sense]--this coming from a man with a head looking like a donkey-- for that and yet, to say the truth, reason and love keep little company together now-a-days; [satire by Shakespeare] (III,i,134-135)
This scene is another humorous way for the author to demonstrate to the reader that "love makes fools of us all."
The main reason the romance between these two characters is comical is because Bottom has been transformed into an ass. Titania, the beautiful fairy queen, falls in love with him despite his ugliness. It is the result of Titania's accidentally inhaling the fairy dust intended for someone else,a potion that causes the user to fall in love with the next being they see. Titania is portrayed as proud and strong-willed, so the notion that she would be so easily manipulated by magic is also humorous. As well, Bottom is a character of lower social class, and Titania is royalty among the fairies, so this is also comical because of the intermingling of these different social classes. Titania's language is also funny as she keeps referring to the beauty of Bottom and her undying passion for him.