Here the beautiful niece of Professor Coffin, the lovely Arachne. She was the eye-catching hostess of Midnight Tales alonside her academic uncle Professor Cyrus Coffin. This tempting double-spread poster was included in the fifth issue of Wayne Howard's Charlton tour de force. I found it here.
Here's the cover to that issue. Howard could sure draw some tempting dames, but he couldn't draw a top hat at all.