We present a phantom-receiver-based routing scheme to enhance the anonymity of each source-destination pair (or contextual privacy) while using an adjustable amount of overhead. We also study how traditional network coding and opportunistic routing can leak contextual privacy. We then incorporated both network coding and opportunistic routing into our scheme for better network performance and show how we mitigate its vulnerability. Contrary to prior works, we allow the destination to anonymously submit an acknowledgment to the source for enhanced reliability. Performance analysis and simulations are used to demonstrate the efficacy of the proposed scheme against commonly considered traffic analysis attacks.