Why is the master's permission required for a partially freed man to marry, but not necessarily for intercourse with a partially owned slave woman?

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Intercourse with a partially owned slave woman is permissible without the master's consent because no right of the master is attached to her in that specific act, nor does it cause detriment to the master's interest, analogous to using her for service. However, marriage imposes obligations upon his entire being, thus requiring the master's consent so that the master agrees to the attachment of rights to his remaining property interest. In contrast, the right exercised in intercourse is for the partially freed man himself, not against the master's property rights.