They're so perfect, it's nauseating.
The only potential problem for this impossibly good-looking new couple? DiCaprio is 36 and Lively is 23, creating a sizable 13-year age difference.
DiCaprio also happens to be on the rebound. He just split with 25-year-old Israeli supermodel Bar Rafaeli, and they're known to be on-and-off.
"They do this every two years," a source told Us Weekly. "They could be back together next week."
In the meantime, from Leo and Blake to Brangelina to Gisele and Tom, let us know: Who's the sexiest celeb couple?