Compose a song, line by line It's time for CGCC to demonstrate our musical talent! In this challenge, you're going to compose songs while keeping your byte count as small as possible.
On Day 0, multiple answerers will post a function or program that outputs nothing/an empty string. They will also give a single line that next day's answers must output. More lines will be added to that line later, gradually building up a song. I'm not starting off Day 0 myself because letting multiple people answer will allow for more variety later.
On Day 1, answerers will choose an answer from Day 0. They will post a function or program that outputs the line from the Day 0 answer. This will be the song for the next answer. Like on Day 0, Day 1 answerers will also give a single line that next day's answers must add anywhere to their song.
On Day i, answerers will choose an answer from Day i-1 with partial song s and line l. They can now insert l between any two lines in s or put it at the start or end of s. This will now yield a new partial song that each must write a function or program to output. Again, answerers will also give a line for next day's answers to add to their partial song.
Rules
The rules have been changed, please see the bolded parts below. Sorry for the inconvenience.

New lines can be put between other lines, at the start of the song, or at the end of the song.
Lines may be repeated.
Lines must be at least 20 characters and at most 100 characters.
You may have trailing spaces at the end of each line when printing the song.
You may have multiple answers on a single day and you may answer on consecutive days, but you cannot continue from your answer on a consecutive day.
This isn't a hard rule, but if you take your line from a song, please link to it.
The day changes at midnight UTC+0.
Your score is the average length, in bytes, of all your answers (not including answers on Day 0), divided by the number of answers you have posted (this is a change from before, but the objective is still the same - make your answer as short as possible).

It is currently Day 19.
Examples
Note: These examples are just to show the format of each answer; they are not good examples of the kinds of songs you should write, as they lack creativity.
Day 0. Python, 0 bytes

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Line for next day: Superman got nothing on me (from One Call Away)
Song:

Day 1. Foobarbaz, 7 bytes
DOSTUFF

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Previous answer
Line for next day: I can eat more bananas than him
Song:
Superman got nothing on me

Day 2. Foobarbaz, 11 bytes
DOMORESTUFF

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Previous answer
Line for next day: And I'm never gonna give you up (modified from here)
Song:
Superman got nothing on me
I can eat more bananas than him

Day 3. somelanguage, 3 bytes
foo

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Previous answer
Line for next day: That's the only thing that matters
Song:
Superman got nothing on me
I can eat more bananas than him
And I'm never gonna give you up

A possible song for day 4 (note that the new line was inserted this time instead of being appended):
Superman got nothing on me
I can eat more bananas than him
That's the only thing that matters
And I'm never gonna give you up
Day 0. Java (OpenJDK 8), 5 bytes

a-&gt;&quot;&quot;

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The line for tomorrow is Baka mitai kodomo na no ne.
thanks to caird for reminding me i don't need to submit a full program lol