Oberon and Titania's quarrel has set nature in imbalance, causing drought and famine. The quarrel is ostensibly about the Indian boy, but jealousy underlies the relationship between these two rulers of the fairy world. Both have promiscuous pasts, and they have had amorous relationships with Theseus and Hippolyta, rulers of the human world. Sexuality seems pushed away from the human sphere in this play and kept within the world of fairyland instead.
The way in which the quarrel between Oberon and Titania is resolved is quite odd: Oberon forces Titania to love a creature half man, half donkey. While she is under this spell, Oberon asks her to give him the boy, and she does so without any further complaint (IV i 56-60). When he takes away the spell, Titania is happily his again, disgusted at the monster she has loved (IV i 75).
According to Harold Brooks, Oberon is a mentor to the lovers, setting confusion straight and helping them to find their true couplings. He also sees Oberon as a mentor to Titania, and this is more provoking:
Towards Titania he is again from one point of view a mentor: he takes charge of her experience in order to guide her into change of attitude. (..) His move against her is designed to reunite her with him; on his own terms, certainly, but it is of course she who is principally at fault. (..) [I]n preferring [the Indian boy] above her husband Titania has got her priorities wrong. (Brooks 1983: cvi)
Brooks echos the conventional view, that Oberon should have the boy to allow him to pass into the manhood and escape Titania's "maternal dandling" (Brooks 1983: cvi). Other critics (among others Kott, Boehrer and Garner) have questioned why Oberon is so eager to have this boy, suggesting homoerotic overtones to his desire.
about Oberon making Titania fall in love with a donkey