If Anko has spent her whole, very long, life alone, it seems to me it shouldn't be impossible for Second to simply make her enjoy the presence of company gradually. It might be overwhelming in the beginning but if done a little by little, I reckon she would come to love it. She's a wolf, after all, and wolves are social pack animals. That's why "lone wolf" is a concept, because it's fundamentally a contradiction, thus underlining a special case. Her existence thus far has been abnormal, yet she has been forced to get used to it. Second just needs to fix it. Maybe she can interact with Eco first, since Eco is quite animalistic as well. Definitely not Yukari because Anko would likely just be pissed off by lectures and menial tasks, plus she probably won't take orders from anyone but Second.