itch.io

Visual novels are interactive stories. They focus mainly on character development and plot rather than action and gameplay mechanics.

Resources relating to or for building Graphical User Interfaces (Commonly called GUIs)

An otome game is a story based video game that is targeted towards the female market. Generally one of the goals, besides the main plot goal, is to develop a romantic relationship between the female player character and one of several male or female characters.

http://en.wikipedia.org/wiki/Otome_game

Ren'py is a free and open source Visual Novel Creator.

Focused on using its text, moreso than its visuals or audio, to tell the bulk of its story/plot. (Still can have great audio and visuals, though!)

Unity is a game engine for 2D, 3D, AR and more

Resources for building and relating to User Interfaces, how the user interacts with your program