Since this is just a demo, the story branches get cut midway.
The two main mini-endings are either getting a scene illustration with Alex (kissing) or him not kissing you. Either way, he doesn't want to hang around.
To get the kissing illustration, it's pretty easy. Don't act like a jerk to Alex. Like hard liquor (avoid the midori sour, people) and be a bit cocky, but not an asshole.
The endings with Ian and Penny will all be in the full game. (Incidentally, have you supported the project yet for the full game? Why not?!? XD)
If you "DIE" in the demo, you wind up becoming an impoverished Visual Novel maker working on a gay dating sim. I should have added that you also end up trying to run a Kickstarter to fund your game...but it was already messing with my head a little.
If you "ALMOST" die in the demo, you end up getting breaking the fourth wall, and Mark comes over to chat with you, basically upset you are trying to go out of the bounds of the demo. Do this six times throughout the demo and you end up getting busy with Mark. (It's just a brief dialogue exchange though, no pictures, so don't get too excited.)
These are the points at which the fourth wall gets broken:
1st chat with Mark:
Instead of coming out, remind them about the toilet paper
"Well yeah, I'm just tired of having.."
(It doesn't matter long-term how you respond to Mark when he pops up and tries to redirect you...though you will get different reactions from him).
"Well, Ok. I'm gay." (To keep you from Dying.)
2nd chat with Mark:
In the living room, when Penny wants to drag you to the gay bar
- Eh, I don't feel up to it.
- No. I want to stay in.
- I do what I want!
- Pick either "sure what's the problem" or "really? Again?". They don't affect any long term scores.
- Pick either dialogue option. No long term effects.
- Ok, GEEZ, I'll go to the gay bar!
3rd chat with Mark:
After your first day of class leaving lecture, choose "Keep Walking" twice
- Mark appears. It doesn't matter how you respond to him. (Would a psychopath really say 'yes?')
- Turn around
4th chat with Mark:
When Ian wakes you up in your bedroom after your dream
- "Ian, enough with your armchair psychoanalyzing"
- "Nah, man."
- Mark appears. Pick either choice. There's no longterm effect.
- Go to the gym with Ian.
5th chat with Mark:
Second time Ian wakes you up
- "It's two Saturday mornings in a row..."
- "Look, I can find dates just fine"
- When Mark appears, (say nothing) if you don't want anything to culminate between you and him later. Choose "You've found me out" if you do.
- Go the gym
6th chat with Mark:
When you avoid Alex at the gym for the second time with "Not feeling it today" and "Sorry but no", it will be the same deal
- Depending on what you did during your 5th chat, you'll either get a brief comment from Mark or the suggestion of something more. I really wish I could have put a scene illustration here but...time and money and all that! Maybe for the future. :D