The act of self masturbation (generally by females) upon sight of their sexual partner to the point of extreme moisture in the vaginal area. The name Squishy Love comes from the audible sound created during the act.
Jill's boyfriend returns home. Jill see's him, leads him to the bedroom where she then masturbates furiously, creating the aformentioned 'Squsihy' noise.
The boyfriend tell's his friends what happened and could only describe the act as Squishy Love.