Group with Joey.

Frogs are in the toilet. By disturbing the water flow, you can hear the frog’s noise. They don’t like you disturbing their silent life. The more you disturb them, the more noisy they are. The only way to stop the noise is to kiss frogs.
If you kissed it, the noise will be shut down and by disturbing the water flow, you can hear the sound of them dropping into the river.

I faked the PIR senser as kissing sensor because it was just detecting movement. So when the mouth is approaching, the sensor can detect it. I also use the beam senser for detecting the movement of hand. Only when the beam is shot twice that the act is consider as one time of disturbance of water flow.
I also tried to combine two sensors in other ways but failed. Mainly because PIR is really slow movement detection and beam is high frequecy movement detection. I haven;t thought of a good way to combine them.