This is the very last extra of the very last volume (13) of Taiyou no Ie. There are a couple more longer extras before but the scanlators are working on them and you can read them translated on
Mangalator Otakumole if you can’t wait till then. This little extra was not in the magazine though and it’s only a few pages long so I’m putting it up. Also there’s no need to understand Japanese for this XD
If you ever wondered if and/or how the hell Mao and Hiro would ever be able to go past holding hands and chaste kisses, this extra is your answer.
Poor Hiro. Then again it’s also a good thing that Mao is not as bashful as she seems.