That first half of the episode was just amazing. The dialogue between Yasako and Isako was just right, and I actually cried when Isako started to break down. Yasako really tried to comfort Isako in the way she would speak to Kyoko, whenever she’s scared. When Kyoko arrived, and asked Isako to save Densuke, she only made things even better.
The rest of the episode built up for the final few episodes of this series. We get a few confirmations of things that the observant ones among us probably already figured out: Nekome and Takeru are brothers, Takeru is the owner of the pink cat with ears, and he basically betrayed Isako out of jealousy towards his brother. I’ve also been reading a few posts from animesuki, and it seems that the reason why Nekome has access to the stronger versions of the Sacchis is because he works for the government, and can basically use them as he pleases.
Also, Densuke indeed is no ordinary dog. I couldn’t catch the details due to my lack of Japanese, but there actually is a chance for both Yasako’s grandfather as 4423′s brother to be alive. Yasako’s grandfather also seemed to know about 4423 before both of them disappeared. The final parts of the episode basically consist out of a chase for Densuke, after Nekome found out that he’s important somehow I must say that it was awesome to see Daiichi in action again. From what I understood is that Densuke is the key to access Coil’s domain, which is what I suspect to be the place where the humanoid illegals live. Hence why both Yasako and Kyoko encountered them.
What’s also interesting is how Nekome refers to Yasako as “sensei”, and how a password to some of the guy’s secret stuff is located inside Nekome’s database. Does this mean that Yasako’s grandfather used to work for the same company that Nekome is working for?