be soft on (someone)
1. To treat someone delicately, gently, or leniently; to not criticize, punish, or berate someone too harshly. You should be soft on Bill, it's his first day in the office. You're too soft on those kids. They need more discipline or they'll get out of control!
2. To be romantically interested in or infatuated with someone. I think John's soft on Samantha, I hope he asks her out on a date!