Oberon and Titania, King and Queen of the Fairies, are used by Shakespeare to explore the darker, more passionate side of love throughout the play. Their meeting at the beginning of Act II sets up the stormy, jealous nature of their relationship with accusations of infidelity on both sides. Oberon accuses Titania of a liaison with Theseus, whilst Titania believes him guilty of flirtation with Hippolyta.
The repercussions of their tempestuous quarrels upon the natural world are laid out, as Shakespeare suggests that freak weather - fogs, floods - ensues from their falling out (Act II, scene 1). Titania's refusal to bend to Oberon's will provokes a jealous rage in him, causing him to bewitch her and force her to fall in love with Bottom against her will (Act II, scene 1). His desire is to humiliate and control her.
Even jealous love knows its limits, however, and Oberon regrets his acts as he sees their consequences (Act IV, scene 1). He releases Titania from her enchantment and the pair are reunited, restoring order upon the mortal world, and bestowing blessings and good fortune upon the three couples (Act V, scene 1).