There's some serious breast expansion in a Japanese anime called The Qwaser of Stigmata. It occurs in episode 21, just a little under 8 minutes into the second half at this site. The storyline doesn't make a lot of sense. It's anti-Christian but in a way that accuses Christ of all kinds of crazy nonsense, as if the Apostles were vampires or something. But it has lots of big tits and some breast expansion, so whatever.
Gotta give it up on this one - it's a really good breast growth video morph of a scene from "Princess Lover".
I love the tagline for When Expanding Worlds Collide - "A shy boy's life dramatically changes when his friend gets a magical DVD that produces a bosomy girl."
In issue #3, we finally get to see a slender Japanese girl transform into her magical warrior form. She goes from small and flat to tall and stacked with just a few magic words.
And then she forces herself sexually on the "shy boy" who needs a good lesson in titty fucking, apparently. Check out the free sample at the Breast Expansion Story Club.
[When Expanding Worlds Collide #3 - Free Sample - BE Story Club]
Haruhi Suzumiya's wish by ~DrCromdor on deviantART
DeviantARTist DrCromdor likes to draw familiar anime and manga characters with their breast sizes increased to the upper range of normal development. In this one, he augments Haruhi Suzumiya's small boobs into a very decent set of jugs!
Sometimes I wonder if the Japanese aren't merely from another country, but actually from another planet. Still, a video game that allows players to make characters' breasts grow is pretty cool. And yes, in Pai Touch!, that actually seems to be the main plot thrust of the game - give the girls huge tits. Here's the producer's web site.
[h/t: NinjaBunneh]