What does "butt-balling" mean?

What's "naked eye" mean? Can I use with other body parts too? Like "naked hands"

"Naked eye" means unassisted vision. You can see something without a telescope, binoculars, or some sort of vision-altering tool. It's considered different from phrases like "naked body" or "naked hands," which would just describe a body or hands without clothes on it. Ex: On a clear night, you can see Jupiter with the naked eye. Ex: The naked eye can't see all the pollution in the air. Ex: My feet felt naked after having shoes on for so long and finally taking them off.

What's the main difference between a "billiard" and a "pool?"

Billiards and pool are a little different based on how they are played. Billiards is played on a table without pockets and only uses three balls. Pool involves a table with six pockets and involves 9 or 12 balls in order to play. Billiards used to refer to all sports played with cues and although some people still use the terms interchangeably, they are actually different sports.

Can I say "consequence" instead of "result" here?

"Consequence" (and "repercussion") are almost always used to refer to something negative. When you want to talk about the general effects of some action, "result" is usually used. Ex: Every action has a consequence. Ex: The justice system exists to allow criminals to face the consequences of their actions. Ex: I'm very pleased with the results of my exam. Ex: Are you happy with the results of your efforts?

Can "drink" here mean drinking tea or coffee in the cafe? What does "drink" mean?

No, "drink" here means an alcoholic drink. Many people prefer to have a short drink with someone to see whether they'd like to spend more time with them, such as having dinner together. That way, they can leave quickly if the date does not go well. If the drink being referred to is a coffee or tea, then the speaker would have used "coffee." Ex: I have a coffee date tomorrow. Ex: I'm having a drink with a guy from Tinder.

Is “is” after “house” omitted?

I don't believe so. The sentence before this one is "How did you find me here?" When he says "the house in front of the library," it works well with the prior sentence. "The house is in front of the library" would not work here because she didn't ask where the house was.