I don't recall what to do to get the specific ending, but I remember the basic rule behind it.
the game is split into 2 parts, the first 'fake' ending (with the glitched screen), and the second 'real' ending.
You have 2 choices to make:
1. Ignore her in every choice.
2. Talk to her in every choice.
Using this information, the 4 endings are:
1. (Ignore, Ignore)
2. (Ignore, Talk)
3. (Talk, Ignore)
4. (Talk, Talk)
Where the first item is the course you play for the first part (Till the fake ending), and the second item is the course you take for the second part.