Imagine Nick Nugent’s surprise when, during the first session of his popular international marketing course at Boston College, the professor looked up to see Los Angeles Lakers star Kobe Bryant wander in. “I had just begun the class with an example of how the NBA is a model of successful international marketing, and how Kobe is its biggest star, when suddenly the door opened,” said Nugent (above, with Bryant). “It was surreal.” Though not playing because of an injury, the five-time NBA champ was in town for Friday’s Lakers/Celtics game at TD Garden. Nugent said Bryant sat down with the rest of the students, took notes, and even asked a question. During a break, Bryant was asked if he knew Nugent. “I know of him,” said the Laker, who hung for the whole two-hour class and then signed autographs and posed for photos with students. “I didn’t go to college,” Kobe told the kids,” but I love to learn and international marketing is something I’m interested in.” (Bryant was just out of high school when he was drafted in 1996.) Afterward, Bryant tweeted: “Learn, Learn, Learn. Thank you #BC #internationalmarketing, Education never stops.” For his part, Nugent, who’s taught at BC for 27 years, said it was an experience he’ll never forget. “The only difficulty will be next week when I try to top our first class,” he said.