Your skepticism about advertising for a relationship without a commitment is warranted, but I would counter that if such an arrangement was desired there is hardly any better place to advertise. It is rather unlikely I would find one within the confines of society.
You describe yourself as opinionated and untraditional, but suspect your mail is filtered? Should I be concerned about getting into trouble with some overprotective family members if we continue corresponding?
[he addressed the envelope as she requested!]