There is a picture of a diode in the block diagram of R1191, but is the diode actually inserted?

The block diagram of R1191 includes a picture of a diode to make it easier to understand how the reverse current protection function works. It does not mean that a diode actually exists in the device. 

Although we cannot disclose the details, the power supply voltage VDD is compared with the output voltage VOUT, and if VDD < VOUT, the Pch driver is turned off. At the same time, the direction of the parasitic diode of the driver is switched. 

Note that the block diagram of R1163 and RP115 also shows a picture of a diode, but the same concept as this product can be used.