Help me with these expressions!!

Thanks for your kind answers. Here comes another questions.

1. You've gotta get over to the manse, tout-de-suite.

What is 'tout-de-suite'? It sounds like some kind of French.

2. You know what would bring it down a notch? Some Hawaiian Punch and a chocolate cigarette.

What is 'bring it down a notch'? I think this is sort of an idiom.

3. We are here to get my kid some tail.
What is 'get my kid some tail'? I looked for 'tail' in a dictionary, and one of the meaning is 'a girl'.
Therefore I think this means they are trying to hook a girl with his kid.

4. So you didn't make the kill. That doesn't mean you can't feed on the carcass.
I have two questions. 'make the kill' and 'feed on the carcass'. In this situation, a boy was afraid to ask a girl out, and his father said this thing. I get just some rough idea, but don't know what exactly this means.

What is 'tout-de-suite'? It sounds like some kind of French.

It is French and means 'immediately'. It is used occasionally in English.

What is 'bring it down a notch'? I think this is sort of an idiom.

A notch is used in the sense of a 'level' or noticeable amount.

Tail = a girl, in a sexual manner.

It's not clear to me what the father means. I suppose he's trying to console the son. The expression means that you might not be the person who got the result, but you could gain some benefit from it. ;-)