Hernan Bas has been living in Venice this year, painting tourists. He’s aware of the ironies. (He is the kind of tourist, he tells me, who started looking at Venetian property prices, oh, about a week into his stay.) The Cuban-American artist is from Miami, and he knows about mass tourism all too intimately: he lives in an neighbourhood that has now been so thoroughly colonised by Airbnbs that when he comes home from the airport, taxi drivers ask him where he’s visiting from, and he has to explain that no, this is his own house.

Here – his studio looking out over the lulling lap of the lagoon – he can be the tourist as innocent, as amnesiac, drinking in the beauties of the city and forgetting about the violence and catastrophe unfurling beyond. “I can pretend nothing’s happening in the world. And I’ve done a very, very good job of that for the last seven weeks,” he tells me when we meet in the spring. For a moment his mind drifts back despairingly to his home town and the fraught politics of his country. “It was so mind boggling how much the Latin community went for Trump, and now everyone is eating dirt because they’re hiding from ICE,” he says. “Those same people who were gung ho for Trump are now getting deported.”

Bas’s tourists form a body of work that will be seen in the Ca’ Pesaro, the city’s modern art museum: an exhibition of 30 paintings that will open alongside the Venice Biennale. He shows me some of them – in tone ranging from the bleak to the gently satirical. Here is a grinning young white man at Holi in India, the festival that marks the end of winter with a celebration of bright colours – he is smeared in pigments, “my excuse to paint like Willem de Kooning for a day”. Here is another youth cradling a koala: Bas stumbled on an entire corner of the internet devoted to celebrities nursing these marsupials (an activity now outlawed in parts of Australia). His painting is loosely based on an image he found of Harry Styles. At the darker end there is a grinning young man begging on the streets for help to get to Ko Pha-ngan for a full moon party (the Thai island is home to the beach of Leonardo DiCaprio and White Lotus fame). Another has a young man offering hugs in exchange for a tip to support his travels. The series is called not The Tourists but The Visitors – a title that tunes into the slightly sinister, uncanny aspect of some of these works. The young men are like aliens; they might have dropped by from outer space.

The figures in the paintings are all young men – young white men. It has been similar throughout his career. Occasionally a woman creeps in, but for years he has painted youths in various highly wrought fantasy or fictional settings: youths fishing amid a night landscape; or crouched amid sunflower fields, a young man reclining on a couch in the pose of an expiring dandy. Part of it is, he admits, because “I’m gay, and these are the kind of pretty people I would be attracted to.” They “are all just Holden Caulfield from Catcher in the Rye to me: it’s the cliche of the youth who doesn’t know where he is in life. I’ve basically been painting that character for my entire career.”

It’s the narrative, the story of the painting that really attracts him, he says. “People make fun of me for saying it, but I always feel like everything I do is an attempt at being a conceptual artist who just happens to paint. The idea, the scenario is the hardest thing for me to come up with. I could just paint pretty boys all day and get away with it at this point in my career, but that doesn’t interest me at all. Something has to be in the painting: some kind of narrative.”

For each of these tourist paintings, he has gone deep down a rabbit hole of research, coming up for air sometimes aghast at the human folly he has discovered. “I love storytelling,” he says. “I thought I wanted to be a writer more than I wanted to be a painter at certain points in my life. When I sit around with these characters I have to make entire backstories about their lives that no one will ever know about, that only exist in my brain.”

Another recent series, called The Conceptualists, consisted of somewhat satirical paintings of handsome young men, each of them an artist with some faintly ridiculous practice. “I invented the stories of these different characters from scratch, as well as the entire body of work of each of them.” He thinks of his way of working as something like “stagecraft”, creating a small compressed drama in which “you’re building a play-set, and you have to be able to describe the entire play within one glance.” For the current series, each painting is accompanied by a little text – sometimes invented by Bas, sometimes spliced together from, for example, real TripAdvisor reviews culled from the web. “Some of them were too funny not to use,” he says.

Still, even if he’s poking fun at tourist cliches – and even expressing a certain disgust, at times – he’s still a generous fellow. In Ca’ Pesaro, his work will be installed in a room overlooking the Grand Canal, where two large windows, usually concealed by curtains, have a wonderful view to the water. When his show is on, though, he has asked for the curtains will be drawn back. “I want people to really have that tourist moment,” he says, “even if it means ignoring what I put 10 months of my life into. The show is in Venice for a reason.”

• Hernan Bas: The Visitors is at Ca’ Pesaro – International Gallery of Modern Art, Venice, 7 May to 30 August