When grinding on Destiny Island i have found fighting Selfie for tech points to be the best. When she raises her hand over her head and then leaps at you to atack, you reflect her rope attack back and then move away a short distance and face her again. This will cause her to repeat the same attack over again. Each time you will recieve 2 tech points one for reflecting and another when her rope hits her on the head. However selfie cannot be Knocked out from tech points so as long as you dont strike her yourself you can repeat this strategy infinitely till your bored, slip up or are at your target level