Hello Jake!
The F/Interact Key will come into play during regular gameplay once more friendly NPCs are added, we have our first coming soon as it's one of our higher Patreon reward tiers and we have one lined up! We planned to use Kobolds as an example for how the feature would work on the training stage.
Pledging give you access to all 12 enemies (Instead of about 4) and most now have 2 sex scenes each. You can get these in the gallery and ingame with the Patreon password. You can find the new build here! https://jasonafex.itch.io/bare-backstreets/devlog/382008/new-public-build-v066