bill and coo
US /bɪl ənd kuː/
UK /bɪl ənd kuː/

1.
arrullarse, hacer arrumacos
to show affection by kissing and caressing, often in a public or overly sentimental way
:
•
The young couple was billing and cooing in the park.
La joven pareja estaba arrullándose en el parque.
•
I can't stand to watch them bill and coo all the time.
No soporto verlos arrullarse todo el tiempo.