Our best selves look at Lieu Nguyen’s bursting cherry-blossom tree and start to fantasize about a splendid little world inside it where many creatures run happy and wild through the blooming pink petals, frolicking in an endless childhood. Then we put our naughty cap on and start to imagine that this is what Scarlett Johansson’s pixelated pink-pantied butt might look like if the camera were to zoom in very, very close during that opening scene from Lost in Translation. Either way (and depending on who you are), there are a lot of puerile fantasies to be had here. Nguyen hangs among hundreds of emerging artists at the Affordable Art Fair that opened today and runs at the Altman Building and the Metropolitan Pavilion through Sunday. —Emma Pearse