The disclosure relates to an ejaculatory stimulation device for medical semen collection and personal-use hygiene applications. Conventional devices may be prone to accidental detachment during operation and may be inconvenient to disassemble for cleaning or replacement. The device includes a drive assembly with an exterior contact surface and a detachable movable assembly having a massage member with a massage channel, where the movable assembly reciprocates along a first direction aligned with an inserted phallic structure to provide frictional stimulation, and is released from the drive assembly by movement in a different second direction, such as rotation, while remaining outside the housing. This arrangement can improve operational stability, facilitate removal and maintenance, and help reduce liquid ingress into the drive assembly.