SBS is a general in the first state that is going to fall
Unless he joins Qin or another state who is he fighting for?
Look at Man’U after his state was destroyed. He fought for no state but he continued fighting regardless. He didn’t stop fighting until the people he was fighting for were all dead. Shibashou could be similar. He would fight to keep Qin away from his beloved Seika.
I don't know how Qin just leaves SBS alone when they conquer Zhao
Why would they
not leave him alone quite frankly lol? Shibashou only cares about Seika, why would they continue to send armies after him when he’s just hanging out in Seika not hurting anyone?
If I’m Qin, I ain’t sending anybody for Shibashou lol, just let him die naturally of old age in 40 years. Maybe send minor armies to Seika just to wear them down and by the time Shibashou dies, Seika is exhausted and isolated and ripe for fall.
That’s how Shunshinkun fell Man’U’s and Sentoun’s states, he didn’t send any big names for them, he just continued to wear them down via continuous numbers until their kings realized defeat was inevitable and surrendered on their own. Qin could Shibashou the same way, only sending smaller armies for him but continuing to politically isolate Seika and starve her out.
Until EOS Ousen comes along with his own Kingdom and reaches out to Shibashou with political aid