Congratulations! You finally found a way to get the introvert to talk. Your next task: get the introvert to stop talking.
More seriously, introverts generally hate small talk, seeing it as a waste of time and mental resources. Getting them talking about something they actually find interesting, however, can lead to the opposite problem.
Alanis, killed by a filibustering schoolgirl
So... XX-kun, who's your... your favorite...?
Man... e-everyone's so cool, it's hard to pick, right...Ah... XX-kun...T-that manga I lent you yesterday... what'd you think...?Ah! So you did read it!Y-you know, that manga... i-it's one of my... my favorites...The foreshadowing is so good, and the ca-... the cast is, like, super hot...!I... my favorite character is the protagonist's rival that shows up in the second volume...
Oh, whoops... sorry... spoiler alert, heh...