There are two secret endings featuring the unaligned characters. Under Options, select Opening, then highlight Play. Then:

For the first ending (Diao Chan sings with back-up dancers, Zhang Jiao plays with fire, Lu Bu leers at Dong Zhou) - hold in L1 and R1 and press X.

For the second ending (Zhu Rong sings without dancers, much more silly dancing, Dong Zhou hits on random female) - hold in just L2 and R2 and press X.