You can't spot reduce but have you ever noticed how area of the body with more blood going to them slim first or are slimmer, like limbs you move especially.. lower arms, lower legs but not upper arms or your hips
You have to start working your arms so when you lose the weight all over you will be more toned, Ive seen my arms become more toned since I started lifting maybe 6kg in loads of dif positions and not manish arms because I don't have the hormones to bulk up like that naturally nor will 2 mixed sessions a week make your arms into noticeable muscle lol so dont worry.
Oh and the more you work out your muscles the more calories you will burn 24/7.. is a lot more helpful than cardio alone!