I recommend red strings, as it matches the sides of the frame which are also red and also the bold "VOLTRIC 70" letters on the shaft. Strings which come in red include NBG98 BG65Ti and BG70Pro.
I honestly have not tried pink strings before. And the only Yonex string I can think of which comes in pink is BG65Ti, which is not my favourite or what I would recommend either. It may be hit or miss for you. If you think it would complement the colour scheme of the racquet then perhaps it will work. Individual colour preferences per person can vary a lot