Originally the Romans’ answer to Eros, Cupid is typically represented on Valentine’s Day cards as being a small (often naked) cherubic creature with a themed bow-and-arrow, shooting couples in order to induce them to get together.  

So we already have him bookable on indecent exposure, for a start, as well as assault and battery and unlicensed administration of a controlled substance–those ‘magic’ arrows would likely be classified as a narcotic, nowadays.  Additionally, were it to be proved that he had materially assisted in coercing persons who had no intention of sexual conduct to engage in such, it’s entirely likely that he could be booked as acessory to rape.  

It certainly does not look good for Cupid.

Though his victims are unlikely to press charges–they’re generally depicted as being happy with the results–Cupid would still be regarded as a danger to society.  Getting a conviction might be difficult, given the usual overwhelming support for his mission, but his reckless assaults on various persons would eventually lead to some kind of difficulties–probably from an ex-wife or ex-husband, upset over Cupid’s “theft” of his or her lover.  Even if criminal charges were avoided, the civil suits would be ruinous–there would likely be some kind of class-action suit brought in at least one jurisdiction.  

At the very least, Cupid would end up with hundreds of restraining orders, injunctions, and other legal strictures preventing him from carrying out his job at all.  Given the nature of his crimes, there’s no doubt that he’d end up on the sex offender registries in any state that he made his home.  That would lead to further strictures–no residence within a given number of yards of schools or churches, no unsupervised contact with children, etc.

Were he to actually go to prison, his small stature and youthful appearance would not serve him very well–he would come out very badly if he were in the general population, and would likely have to remain in solitary confinement for his own protection.

All in all, Cupid would not integrate very well in the modern world.