Disco Pigs

Pig and Runt were born moments apart in the same hospital in a small Irish community. They grew up next door to each other and became inseparable friends while they were still toddlers; at the age of 16, their bond is even stronger than ever. However, they also have a fondness for making trouble, and over the years Pig has developed a taste for violence; one of his favorite pranks is to have Runt flirt with a man at the local disco, and then storm up, posing as her jealous boyfriend, and start a fight. Several people in town feel there's something not entirely healthy about Pig and Runt’s relationship, and Runt's parents are persuaded to send her away to a school in the northern part of Ireland. Pig's attachment to Runt grows only more intense in her absence, and in time he runs away to find Runt and bring her back, only to discover she's made a new best friend, Mags … (Mark Deming, All Movie Guide)