This allows you to get Minamo’s other ending, not Mio’s 2nd ending (which needs to be obtained before you can select ‘Choose the days with Minamo’). I think you’re missing one of Mio’s endings (probably the one where you see her 3rd H-scene).
For some reason both gamefaqs walkthroughs seem to be wrong here
a) listen
b) don’t pick up handouts
c) lend her your life force
d) run away
e) patience!
f) to be honest
g) catch her
h) pinch your cheek
i) get away
j) comfort Minamo
k) dash and shake her off
l) go back to the hospital
m) flirt with Minamo
n) listen to Minamo
o) decide now!
p) indulge yourself
q) mystify
r) stop Minamo
s) with Mio
t) don’t say a word
u) stop Minamo
v) tell her what you think
w) Don’t confess (for some reason, both walkthroughs mistakenly had this choice as ‘confess’).
x) I still love Mio
Isn’t the Mio ending only a 50% ending?
At least in this ending you have one girl in each arm (if I remember correctly).