Time for some theorycrafting!
I think it's Ichika helping Miku stealthily throughout the chapter. Consider the following:
The lingerie that Miku got was probably from when Itsuki said she was going to throw it out from the previous chapter. She could have said something like "Instead of...
Super cute chapter, but there's one thing I didn't understand.
Is he shaking so hard that it seems like the phone is ringing or was it actually ringing?
Edit: Oh, they did say it was live. Maybe one of the girls saw it on television and called?
Also a bit curious about the age thing.
In the first chapter Canaria does say that both she and Cesar are 12. This new chapter says they are now 17. So why does she say "Well not friendlier as a married couple... but as a 10 year long male friend?"
They haven't known each other for ten years...