Very quick hint guide in case you get stuck somewhere. Generally, I recommend saving before choices so you can quickly load back.

ENDINGS:

There are 3 regular endings and one true ending.

Ending 1 can be seen by sticking close to your sweetheart and agreeing with him. Disagree often with their twin and try to avoid them.

Ending 2 can be seen by doing the opposite - stay close to the twin, agree with them, and disagree with the sweetheart.

Ending 3 is unlocked after seeing the above. You will find a new choice available.

Ending 4 - the true end, is available after you see all of the above. A new choice at the beginning will appear.