Sun Dongran may seem very arrogant, like a typical profligate, a complete idiot, but actually, he's quite sharp-witted in some aspects, especially in the casino. Right now, he's setting a trap for Li Yifei, and it's quite an elaborate setup indeed.
At first, he didn't gamble big, just betting around a thousand, but as he started to lose, he began raising his stakes, targeting Li Yifei, as if he wanted to compete with him. Soon, he was betting ten thousand each time.
In the beginning, when Li Yifei saw him betting that much, he wouldn't dare to follow even with a small pair. However, after watching Sun Dongran and Cao Bin compete a couple of times, he seemed to notice their tactics. Sun Dongran always seemed like a fool, fond of bluffing, daring to bet tens of thousands even with just a small pair—clearly, he was just aching to give his money away.